M6: desktop app (tray, two-pane layout, shortcuts, inspector, jpackage)

app/desktopApp/build.gradle.kts

@@ -18,6 +18,8 @@ val desktopTarget = when {
 dependencies {
     implementation(project(":shared"))
     implementation("org.jetbrains.compose.desktop:desktop-jvm-$desktopTarget:$composeVersion")
+    // M6: window-state persistence (window.json).
+    implementation("org.jetbrains.kotlinx:kotlinx-serialization-json:1.7.3")
 }
 
 compose.desktop {
@@ -25,3 +27,55 @@ compose.desktop {
         mainClass = "iris.desktop.MainKt"
     }
 }
+
+// ── M6: native packaging (docs/11 §11.4) ─────────────────────────────────
+// `./gradlew :desktopApp:jpackage` builds a self-contained app image under
+// build/jpackage (JRE bundled). `./gradlew :desktopApp:jpackage
+// -PjpackageType=deb` builds a .deb instead (needs dpkg-deb).
+
+val jpackageInputDir = layout.buildDirectory.dir("jpackage-input")
+
+val fatJar = tasks.register<Jar>("fatJar") {
+    archiveClassifier.set("all")
+    duplicatesStrategy = DuplicatesStrategy.EXCLUDE
+    manifest { attributes("Main-Class" to "iris.desktop.MainKt") }
+    from(sourceSets.main.get().output)
+    from({
+        configurations.runtimeClasspath.get()
+            .filter { it.name.endsWith(".jar") }
+            .map { zipTree(it) }
+    }) {
+        exclude("META-INF/*.SF", "META-INF/*.DSA", "META-INF/*.RSA")
+    }
+}
+
+// Stage the fat jar into the jpackage input dir. A dedicated Sync task keeps
+// the Exec task free of task references (configuration-cache compatible) and
+// prunes stale jars from the input dir automatically.
+tasks.register<Sync>("stageJpackageInput") {
+    dependsOn(fatJar)
+    from(fatJar)
+    into(jpackageInputDir)
+}
+
+tasks.register<Exec>("jpackage") {
+    dependsOn("stageJpackageInput")
+    val jpackageBin = file("${System.getProperty("java.home")}/bin/jpackage")
+    val type = (project.findProperty("jpackageType") as? String) ?: "app-image"
+    val inputDir = jpackageInputDir.get().asFile
+    val destDir = layout.buildDirectory.dir("jpackage").get().asFile
+    inputs.dir(inputDir)
+    outputs.dir(destDir)
+    commandLine(
+        if (jpackageBin.exists()) jpackageBin.absolutePath else "jpackage",
+        "--name", "iris",
+        "--app-version", "0.1.0",
+        "--vendor", "Iris",
+        "--type", type,
+        "--input", inputDir.absolutePath,
+        "--main-jar", "desktopApp-all.jar",
+        "--main-class", "iris.desktop.MainKt",
+        "--dest", destDir.absolutePath,
+        "--java-options", "-Xmx1g",
+    )
+}

app/desktopApp/src/main/kotlin/iris/desktop/Main.kt

@@ -1,13 +1,184 @@
 package iris.desktop
 
+import androidx.compose.runtime.DisposableEffect
+import androidx.compose.runtime.LaunchedEffect
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
+import androidx.compose.ui.awt.ComposeWindow
+import androidx.compose.ui.graphics.painter.BitmapPainter
+import androidx.compose.ui.graphics.toComposeImageBitmap
+import androidx.compose.ui.unit.dp
+import androidx.compose.ui.window.Tray
 import androidx.compose.ui.window.Window
+import androidx.compose.ui.window.WindowPosition
+import androidx.compose.ui.window.WindowState
 import androidx.compose.ui.window.application
 import iris.IrisApp
+import iris.net.GatewayClient
+import iris.platform.DesktopBridge
 import iris.platform.DesktopSecureStore
+import java.awt.Color
+import java.awt.Graphics2D
+import java.awt.RenderingHints
+import java.awt.SystemTray
+import java.awt.event.WindowEvent
+import java.awt.event.WindowFocusListener
+import java.awt.image.BufferedImage
+import java.io.File
+import java.util.concurrent.atomic.AtomicBoolean
+import kotlinx.coroutines.delay
+import kotlinx.serialization.json.Json
+import kotlinx.serialization.json.jsonObject
+import kotlinx.serialization.json.jsonPrimitive
 
-fun main() = application {
+/**
+ * M6: desktop shell (docs/11 §11.2/§11.3).
+ *
+ * - resizable window, size/position persisted to `~/.iris/window.json`
+ * - system tray (Compose Desktop `Tray`): connection-state icon + tooltip,
+ *   Show / Quit menu, close-to-tray (X hides the window when the tray is up)
+ * - window focus drives `DesktopBridge.foreground` (banner vs OS notification)
+ * - OS notifications themselves are posted from shared/desktopMain
+ *   (DesktopNotifier), which also updates the tray tooltip
+ */
+private val windowJson = File(System.getProperty("user.home"), ".iris/window.json")
+
+// Tray icon colors (ARGB). .toInt(): the literals exceed the Int range.
+private const val TRAY_OFFLINE = 0xFF9E9E9E.toInt()
+private const val TRAY_CONNECTING = 0xFFFFC107.toInt()
+private const val TRAY_CONNECTED = 0xFF4CAF50.toInt()
+private const val TRAY_AUTH_FAILED = 0xFFF44336.toInt()
+
+fun main() {
     val store = DesktopSecureStore()
-    Window(onCloseRequest = ::exitApplication, title = "Iris") {
+    val traySupported = SystemTray.isSupported()
+    val closeToTray = AtomicBoolean(traySupported)
+    var composeWindow: ComposeWindow? = null
+
+    application {
+        var trayColor by mutableStateOf(TRAY_OFFLINE)
+        var trayTooltip by mutableStateOf("Iris — offline")
+
+        if (traySupported) {
+            val trayBitmap = remember(trayColor) { trayIconImage(trayColor).toComposeImageBitmap() }
+            Tray(
+                icon = BitmapPainter(trayBitmap),
+                tooltip = trayTooltip,
+                onAction = { showWindow(composeWindow) },
+            ) {
+                Item("Show Iris") { showWindow(composeWindow) }
+                Separator()
+                Item("Quit") {
+                    closeToTray.set(false)
+                    saveWindowState(composeWindow)
+                    exitApplication()
+                }
+            }
+        }
+
+        // Connection-state poller: tray icon color + tooltip.
+        LaunchedEffect(Unit) {
+            while (true) {
+                delay(2_000)
+                val state = DesktopBridge.controller?.client?.state?.value
+                val (color, tooltip) = when (state) {
+                    null,
+                    is GatewayClient.State.Disconnected -> TRAY_OFFLINE to "Iris — offline"
+                    is GatewayClient.State.Connecting,
+                    is GatewayClient.State.Reconnecting -> TRAY_CONNECTING to "Iris — connecting…"
+                    is GatewayClient.State.Connected -> TRAY_CONNECTED to "Iris — connected"
+                    is GatewayClient.State.AuthFailed -> TRAY_AUTH_FAILED to "Iris — auth failed"
+                }
+                trayColor = color
+                trayTooltip = tooltip
+            }
+        }
+
+        // A notification (backgrounded reply / approval / cron) also shows up
+        // in the tray tooltip; the OS notification itself is posted by
+        // DesktopNotifier (shared/desktopMain).
+        DisposableEffect(Unit) {
+            DesktopBridge.onNotification { _, title, _, _ ->
+                trayTooltip = "Iris — $title"
+            }
+            onDispose { }
+        }
+
+        Window(
+            onCloseRequest = {
+                if (closeToTray.get()) {
+                    composeWindow?.isVisible = false
+                } else {
+                    saveWindowState(composeWindow)
+                    exitApplication()
+                }
+                true
+            },
+            title = "Iris",
+            state = loadWindowState(),
+        ) {
+            composeWindow = window
+            window.addWindowFocusListener(object : WindowFocusListener {
+                override fun windowGainedFocus(e: WindowEvent) {
+                    DesktopBridge.foreground = true
+                }
+
+                override fun windowLostFocus(e: WindowEvent) {
+                    DesktopBridge.foreground = false
+                }
+            })
             IrisApp(store)
         }
+    }
+}
+
+private fun showWindow(window: ComposeWindow?) {
+    window ?: return
+    window.isVisible = true
+    window.toFront()
+    window.requestFocus()
+}
+
+/** A simple two-tone circle; the outer color encodes the connection state. */
+private fun trayIconImage(color: Int): BufferedImage {
+    val img = BufferedImage(22, 22, BufferedImage.TYPE_INT_ARGB)
+    val g = img.createGraphics() as Graphics2D
+    g.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON)
+    g.color = Color(color)
+    g.fillOval(2, 2, 18, 18)
+    g.color = Color(0xFF1B1E28.toInt())
+    g.fillOval(7, 7, 8, 8)
+    g.dispose()
+    return img
+}
+
+private fun loadWindowState(): WindowState {
+    return try {
+        if (!windowJson.exists()) return WindowState(width = 1280.dp, height = 800.dp)
+        val obj = Json.parseToJsonElement(windowJson.readText()).jsonObject
+        val x = obj["x"]?.jsonPrimitive?.content?.toIntOrNull()
+        val y = obj["y"]?.jsonPrimitive?.content?.toIntOrNull()
+        val w = obj["w"]?.jsonPrimitive?.content?.toIntOrNull()
+        val h = obj["h"]?.jsonPrimitive?.content?.toIntOrNull()
+        WindowState(
+            position = if (x != null && y != null) WindowPosition(x.dp, y.dp) else WindowPosition.PlatformDefault,
+            width = w?.dp ?: 1280.dp,
+            height = h?.dp ?: 800.dp,
+        )
+    } catch (_: Exception) {
+        WindowState(width = 1280.dp, height = 800.dp)
+    }
+}
+
+private fun saveWindowState(window: ComposeWindow?) {
+    try {
+        val w = window ?: return
+        windowJson.parentFile?.mkdirs()
+        windowJson.writeText(
+            """{"x":${w.x},"y":${w.y},"w":${w.width},"h":${w.height}}""",
+        )
+    } catch (_: Exception) {
+    }
 }

app/shared/src/androidMain/kotlin/iris/platform/Platform.kt

@@ -0,0 +1,3 @@
+package iris.platform
+
+actual val isDesktop: Boolean = false

app/shared/src/commonMain/kotlin/iris/net/GatewayClient.kt

@@ -77,6 +77,10 @@ class GatewayClient(
     private val _state = MutableStateFlow<State>(State.Disconnected)
     val state: StateFlow<State> = _state.asStateFlow()
 
+    /** The paired gateway URL (M6 inspector pane). */
+    val serverUrl: String
+        get() = store.serverUrl
+
     private val _events = MutableSharedFlow<Frame>(extraBufferCapacity = 128)
     val events: SharedFlow<Frame> = _events.asSharedFlow()
 

app/shared/src/commonMain/kotlin/iris/platform/Platform.kt

@@ -0,0 +1,4 @@
+package iris.platform
+
+/** True on the desktop target (M6: big-screen layout, shortcuts, tray). */
+expect val isDesktop: Boolean

app/shared/src/commonMain/kotlin/iris/ui/screens/ChatScreen.kt

@@ -2,6 +2,7 @@ package iris.ui.screens
 
 import androidx.compose.foundation.background
 import androidx.compose.foundation.clickable
+import androidx.compose.foundation.focusable
 import androidx.compose.foundation.horizontalScroll
 import androidx.compose.foundation.layout.Arrangement
 import androidx.compose.foundation.layout.Box
@@ -25,6 +26,7 @@ import androidx.compose.foundation.rememberScrollState
 import androidx.compose.foundation.shape.RoundedCornerShape
 import androidx.compose.foundation.text.KeyboardActions
 import androidx.compose.foundation.text.KeyboardOptions
+import androidx.compose.foundation.verticalScroll
 import androidx.compose.material3.AlertDialog
 import androidx.compose.material3.Button
 import androidx.compose.material3.CircularProgressIndicator
@@ -48,8 +50,18 @@ import androidx.compose.runtime.setValue
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.draw.clip
+import androidx.compose.ui.focus.FocusRequester
+import androidx.compose.ui.focus.focusRequester
+import androidx.compose.ui.focus.onFocusChanged
 import androidx.compose.ui.graphics.Color
 import androidx.compose.ui.graphics.ImageBitmap
+import androidx.compose.ui.input.key.Key
+import androidx.compose.ui.input.key.KeyEventType
+import androidx.compose.ui.input.key.isCtrlPressed
+import androidx.compose.ui.input.key.isMetaPressed
+import androidx.compose.ui.input.key.key
+import androidx.compose.ui.input.key.onPreviewKeyEvent
+import androidx.compose.ui.input.key.type
 import androidx.compose.ui.layout.ContentScale
 import androidx.compose.ui.platform.LocalClipboardManager
 import androidx.compose.ui.platform.LocalFocusManager
@@ -67,11 +79,13 @@ import iris.data.ToolItem
 import iris.net.GatewayClient
 import iris.platform.MediaFilePicker
 import iris.platform.MediaPlayerView
+import iris.platform.isDesktop
 import iris.platform.loadMediaImage
 import iris.platform.openDocument
 import iris.protocol.ChannelInfo
 import iris.protocol.KIND_DOCUMENT
 import iris.protocol.KIND_IMAGE
+import iris.protocol.ROLE_ASSISTANT
 import iris.protocol.ROLE_USER
 import iris.protocol.SearchHit
 import iris.state.IrisController
@@ -110,6 +124,15 @@ fun ChatScreen(controller: IrisController) {
     val drawerScope = rememberCoroutineScope()
     val focusManager = LocalFocusManager.current
 
+    // M6 (desktop): two-pane layout, command palette, inspector, shortcuts.
+    var showPalette by remember { mutableStateOf(false) }
+    var showInspector by remember { mutableStateOf(false) }
+    val composerFocusRequester = remember { FocusRequester() }
+    var composerFocused by remember { mutableStateOf(false) }
+    val railFocusRequester = remember { FocusRequester() }
+    var railIndex by remember { mutableStateOf(0) }
+    val nonThreadChannels = channels.filter { it.kind != "thread" }
+
     fun doSend() {
         val ready = attachments.filter { it.mediaRef != null && it.error == null }
         if (input.isBlank() && ready.isEmpty()) return
@@ -125,28 +148,46 @@ fun ChatScreen(controller: IrisController) {
         if (last >= 0) listState.animateScrollToItem(last)
     }
 
-    ModalNavigationDrawer(
-        drawerState = drawerState,
-        gesturesEnabled = drawerState.isOpen,
-        drawerContent = {
-            ModalDrawerSheet(modifier = Modifier.width(280.dp)) {
-                ChannelDrawer(
-                    channels = channels.filter { it.kind != "thread" },
-                    currentChatId = currentChatId,
-                    onOpen = { ch ->
-                        controller.openChannel(ch.chatId)
-                        drawerScope.launch { drawerState.close() }
-                    },
-                    onNewChannel = {
-                        showNewChannel = true
-                        drawerScope.launch { drawerState.close() }
-                    },
-                    onSetDefault = { ch -> controller.setDefaultChannel(ch.chatId) },
-                    onDelete = { ch -> controller.deleteChannel(ch.chatId) },
-                )
+    // M6: keep the rail selection in sync with the current channel.
+    LaunchedEffect(currentChatId, nonThreadChannels) {
+        val idx = nonThreadChannels.indexOfFirst { it.chatId == currentChatId }
+        if (idx >= 0) railIndex = idx
     }
-        },
-    ) {
+
+    // M6: keyboard shortcuts (docs/11 §11.3) — desktop only.
+    val shortcutsModifier = if (isDesktop) {
+        Modifier.onPreviewKeyEvent { e ->
+            if (e.type != KeyEventType.KeyDown) return@onPreviewKeyEvent false
+            val ctrlOrMeta = e.isCtrlPressed || e.isMetaPressed
+            val overlayOpen =
+                showSearch || showPicker || showPalette || showNewChannel || showNewThread
+            when {
+                ctrlOrMeta && e.key == Key.N -> { showNewChannel = true; true }
+                ctrlOrMeta && e.key == Key.T -> { showNewThread = true; true }
+                ctrlOrMeta && e.key == Key.F -> { showSearch = true; true }
+                ctrlOrMeta && e.key == Key.K -> { showPalette = true; true }
+                e.key == Key.Escape && overlayOpen -> {
+                    showSearch = false
+                    showPicker = false
+                    showPalette = false
+                    showNewChannel = false
+                    showNewThread = false
+                    true
+                }
+                e.key == Key.Slash && !composerFocused && !overlayOpen -> {
+                    composerFocusRequester.requestFocus()
+                    true
+                }
+                else -> false
+            }
+        }
+    } else {
+        Modifier
+    }
+
+    // M6: the chat column (header + list + composer), shared by both layouts.
+    @Composable
+    fun ChatContent(showHamburger: Boolean, onOpenDrawer: () -> Unit) {
         Column(modifier = Modifier.fillMaxSize()) {
             // Header
             Row(
@@ -155,9 +196,11 @@ fun ChatScreen(controller: IrisController) {
                     .padding(horizontal = 8.dp, vertical = 6.dp),
                 verticalAlignment = Alignment.CenterVertically,
             ) {
-                IconButton(onClick = { drawerScope.launch { drawerState.open() } }) {
+                if (showHamburger) {
+                    IconButton(onClick = onOpenDrawer) {
                         Text("☰", fontSize = 18.sp)
                     }
+                }
                 Text(
                     currentChannel?.name ?: "Iris",
                     style = MaterialTheme.typography.titleMedium,
@@ -175,6 +218,20 @@ fun ChatScreen(controller: IrisController) {
                 TextButton(onClick = { controller.cycleToolDetail() }) {
                     Text("tools: ${toolDetail.label}", fontSize = 11.sp)
                 }
+                if (isDesktop) {
+                    IconButton(onClick = { showInspector = !showInspector }) {
+                        Box(
+                            modifier = Modifier
+                                .clip(RoundedCornerShape(8.dp))
+                                .background(
+                                    if (showInspector) Color(0xFF2A3550) else Color.Transparent,
+                                )
+                                .padding(2.dp),
+                        ) {
+                            Text("ⓘ", fontSize = 16.sp)
+                        }
+                    }
+                }
             }
 
             // Topic switcher (threads on)
@@ -276,7 +333,9 @@ fun ChatScreen(controller: IrisController) {
                     onValueChange = { input = it },
                     modifier = Modifier
                         .weight(1f)
-                        .heightIn(min = 48.dp, max = 160.dp),
+                        .heightIn(min = 48.dp, max = 160.dp)
+                        .focusRequester(composerFocusRequester)
+                        .onFocusChanged { composerFocused = it.isFocused },
                     placeholder = { Text("Message") },
                     keyboardOptions = KeyboardOptions(imeAction = ImeAction.Send),
                     keyboardActions = KeyboardActions(onSend = { doSend() }),
@@ -292,6 +351,71 @@ fun ChatScreen(controller: IrisController) {
         }
     }
 
+    Box(modifier = Modifier.fillMaxSize().then(shortcutsModifier)) {
+        if (isDesktop) {
+            // M6: two-pane default (docs/11 §11.3): persistent channel rail +
+            // chat, optional inspector third pane.
+            Row(modifier = Modifier.fillMaxSize()) {
+                ChannelRail(
+                    channels = nonThreadChannels,
+                    currentChatId = currentChatId,
+                    selectedIndex = railIndex,
+                    onSelectedIndex = { railIndex = it },
+                    focusRequester = railFocusRequester,
+                    onOpen = { ch -> controller.openChannel(ch.chatId) },
+                    onNewChannel = { showNewChannel = true },
+                    onSetDefault = { ch -> controller.setDefaultChannel(ch.chatId) },
+                    onDelete = { ch -> controller.deleteChannel(ch.chatId) },
+                )
+                Box(modifier = Modifier.width(1.dp).fillMaxHeight().background(Color(0xFF2A2E3B)))
+                Box(modifier = Modifier.weight(1f).fillMaxHeight()) {
+                    ChatContent(showHamburger = false, onOpenDrawer = {})
+                }
+                if (showInspector) {
+                    Box(modifier = Modifier.width(1.dp).fillMaxHeight().background(Color(0xFF2A2E3B)))
+                    InspectorPane(
+                        controller = controller,
+                        state = state,
+                        currentChannel = currentChannel,
+                        threads = threads,
+                        items = items,
+                        toolDetail = toolDetail,
+                        threadsEnabled = threadsEnabled,
+                    )
+                }
+            }
+        } else {
+            ModalNavigationDrawer(
+                drawerState = drawerState,
+                gesturesEnabled = drawerState.isOpen,
+                drawerContent = {
+                    ModalDrawerSheet(modifier = Modifier.width(280.dp)) {
+                        ChannelDrawer(
+                            channels = nonThreadChannels,
+                            currentChatId = currentChatId,
+                            onOpen = { ch ->
+                                controller.openChannel(ch.chatId)
+                                drawerScope.launch { drawerState.close() }
+                            },
+                            onNewChannel = {
+                                showNewChannel = true
+                                drawerScope.launch { drawerState.close() }
+                            },
+                            onSetDefault = { ch -> controller.setDefaultChannel(ch.chatId) },
+                            onDelete = { ch -> controller.deleteChannel(ch.chatId) },
+                        )
+                    }
+                },
+            ) {
+                ChatContent(
+                    showHamburger = true,
+                    onOpenDrawer = { drawerScope.launch { drawerState.open() } },
+                )
+            }
+        }
+    }
+
+
     // File picker overlay (M4)
     if (showPicker) {
         Box(modifier = Modifier.fillMaxSize().background(Color.Black.copy(alpha = 0.5f))) {
@@ -306,6 +430,8 @@ fun ChatScreen(controller: IrisController) {
     if (showSearch) {
         SearchOverlay(
             controller = controller,
+            currentChatId = currentChatId,
+            currentThreadId = currentThreadId,
             onJump = { hit ->
                 if (hit.threadId.isNullOrBlank()) controller.openChannel(hit.chatId)
                 else controller.openThread(hit.chatId, hit.threadId)
@@ -338,6 +464,32 @@ fun ChatScreen(controller: IrisController) {
             onDismiss = { showNewThread = false },
         )
     }
+
+    // M6: command palette (Ctrl/Cmd+K)
+    if (showPalette) {
+        CommandPalette(
+            actions = listOf(
+                "new-channel" to "New channel (Ctrl+N)",
+                "new-thread" to "New topic (Ctrl+T)",
+                "search" to "Search (Ctrl+F)",
+                "toggle-threads" to "Toggle threads",
+                "cycle-tool-detail" to "Cycle tool verbosity",
+                "toggle-inspector" to "Toggle inspector",
+            ),
+            onAction = { id ->
+                when (id) {
+                    "new-channel" -> showNewChannel = true
+                    "new-thread" -> showNewThread = true
+                    "search" -> showSearch = true
+                    "toggle-threads" -> controller.toggleThreads()
+                    "cycle-tool-detail" -> controller.cycleToolDetail()
+                    "toggle-inspector" -> showInspector = !showInspector
+                }
+                showPalette = false
+            },
+            onDismiss = { showPalette = false },
+        )
+    }
 }
 
 /** Left drawer: channel list + create / set-default / delete. */
@@ -393,6 +545,210 @@ private fun ChannelDrawer(
     }
 }
 
+/**
+ * M6: persistent channel rail (two-pane default, docs/11 §11.3). Keyboard:
+ * ↑/↓ move the selection, Enter opens (when the rail has focus).
+ */
+@Composable
+private fun ChannelRail(
+    channels: List<ChannelInfo>,
+    currentChatId: String,
+    selectedIndex: Int,
+    onSelectedIndex: (Int) -> Unit,
+    focusRequester: FocusRequester,
+    onOpen: (ChannelInfo) -> Unit,
+    onNewChannel: () -> Unit,
+    onSetDefault: (ChannelInfo) -> Unit,
+    onDelete: (ChannelInfo) -> Unit,
+) {
+    Column(
+        modifier = Modifier
+            .width(280.dp)
+            .fillMaxHeight()
+            .focusRequester(focusRequester)
+            .focusable()
+            .onPreviewKeyEvent { e ->
+                if (e.type != KeyEventType.KeyDown) return@onPreviewKeyEvent false
+                when (e.key) {
+                    Key.DirectionUp -> {
+                        if (channels.isNotEmpty()) {
+                            onSelectedIndex((selectedIndex - 1 + channels.size) % channels.size)
+                        }
+                        true
+                    }
+                    Key.DirectionDown -> {
+                        if (channels.isNotEmpty()) onSelectedIndex((selectedIndex + 1) % channels.size)
+                        true
+                    }
+                    Key.Enter -> {
+                        channels.getOrNull(selectedIndex)?.let { onOpen(it) }
+                        true
+                    }
+                    else -> false
+                }
+            }
+            .padding(12.dp),
+    ) {
+        Text(
+            "Channels",
+            style = MaterialTheme.typography.titleMedium,
+            modifier = Modifier.padding(bottom = 8.dp),
+        )
+        LazyColumn(
+            verticalArrangement = Arrangement.spacedBy(4.dp),
+            modifier = Modifier.weight(1f),
+        ) {
+            items(channels, key = { it.chatId }) { ch ->
+                val isCurrent = ch.chatId == currentChatId
+                val isSelected = ch.chatId == channels.getOrNull(selectedIndex)?.chatId
+                Row(
+                    modifier = Modifier
+                        .fillMaxWidth()
+                        .clip(RoundedCornerShape(8.dp))
+                        .background(
+                            when {
+                                isCurrent -> Color(0xFF2A3550)
+                                isSelected -> Color(0xFF232838)
+                                else -> Color.Transparent
+                            },
+                        )
+                        .clickable { onOpen(ch) }
+                        .padding(horizontal = 10.dp, vertical = 6.dp),
+                    verticalAlignment = Alignment.CenterVertically,
+                ) {
+                    Text(
+                        ch.name + if (ch.isDefault) " ★" else "",
+                        fontSize = 14.sp,
+                        modifier = Modifier.weight(1f),
+                    )
+                    if (!ch.isDefault) {
+                        TextButton(onClick = { onSetDefault(ch) }) {
+                            Text("★", fontSize = 12.sp)
+                        }
+                        TextButton(onClick = { onDelete(ch) }) {
+                            Text("✕", fontSize = 12.sp)
+                        }
+                    }
+                }
+            }
+        }
+        Button(onClick = onNewChannel, modifier = Modifier.fillMaxWidth()) {
+            Text("+ New channel")
+        }
+    }
+}
+
+/** M6: optional third pane — session info, channel info, last reply, settings. */
+@Composable
+private fun InspectorPane(
+    controller: IrisController,
+    state: GatewayClient.State,
+    currentChannel: ChannelInfo?,
+    threads: List<ChannelInfo>,
+    items: List<ChatItem>,
+    toolDetail: ToolDetail,
+    threadsEnabled: Boolean,
+) {
+    val lastAssistant = items.lastOrNull {
+        it is MessageItem && it.role == ROLE_ASSISTANT && !it.streaming
+    } as? MessageItem
+    Column(
+        modifier = Modifier
+            .width(300.dp)
+            .fillMaxHeight()
+            .verticalScroll(rememberScrollState())
+            .padding(12.dp),
+    ) {
+        Text(
+            "Inspector",
+            style = MaterialTheme.typography.titleMedium,
+            modifier = Modifier.padding(bottom = 8.dp),
+        )
+        Text("Connection", style = MaterialTheme.typography.titleSmall, modifier = Modifier.padding(bottom = 4.dp))
+        InfoRow("Status", statusLabel(state))
+        InfoRow("Server", controller.client.serverUrl.ifBlank { "— (not paired)" })
+        Spacer(modifier = Modifier.height(8.dp))
+        Text("Channel", style = MaterialTheme.typography.titleSmall, modifier = Modifier.padding(bottom = 4.dp))
+        InfoRow("Name", currentChannel?.name ?: "—")
+        InfoRow("ID", currentChannel?.chatId ?: "—")
+        InfoRow("Default", if (currentChannel?.isDefault == true) "yes" else "no")
+        InfoRow("Threads", threads.size.toString())
+        Spacer(modifier = Modifier.height(8.dp))
+        Text("Last reply", style = MaterialTheme.typography.titleSmall, modifier = Modifier.padding(bottom = 4.dp))
+        InfoRow("Model", lastAssistant?.model ?: "—")
+        InfoRow("Tokens", lastAssistant?.tokens?.toString() ?: "—")
+        Spacer(modifier = Modifier.height(8.dp))
+        Text("Settings", style = MaterialTheme.typography.titleSmall, modifier = Modifier.padding(bottom = 4.dp))
+        Row {
+            TextButton(onClick = { controller.cycleToolDetail() }) {
+                Text("tools: ${toolDetail.label}")
+            }
+            TextButton(onClick = { controller.toggleThreads() }) {
+                Text(if (threadsEnabled) "threads: on" else "threads: off")
+            }
+        }
+    }
+}
+
+@Composable
+private fun InfoRow(label: String, value: String) {
+    Row(modifier = Modifier.fillMaxWidth().padding(vertical = 2.dp)) {
+        Text(label, fontSize = 12.sp, color = Color(0xFF8A93A6), modifier = Modifier.width(70.dp))
+        Text(value, fontSize = 12.sp, modifier = Modifier.weight(1f))
+    }
+}
+
+private fun statusLabel(state: GatewayClient.State): String = when (state) {
+    GatewayClient.State.Disconnected -> "offline"
+    GatewayClient.State.Connecting -> "connecting…"
+    GatewayClient.State.Reconnecting -> "reconnecting…"
+    is GatewayClient.State.Connected -> "connected"
+    is GatewayClient.State.AuthFailed -> "auth failed"
+}
+
+/** M6: command palette (Ctrl/Cmd+K) — all actions, filterable. */
+@Composable
+private fun CommandPalette(
+    actions: List<Pair<String, String>>,
+    onAction: (String) -> Unit,
+    onDismiss: () -> Unit,
+) {
+    var query by remember { mutableStateOf("") }
+    val filtered = actions.filter { it.second.contains(query, ignoreCase = true) }
+    AlertDialog(
+        onDismissRequest = onDismiss,
+        title = { Text("Command palette") },
+        text = {
+            Column {
+                OutlinedTextField(
+                    value = query,
+                    onValueChange = { query = it },
+                    modifier = Modifier.fillMaxWidth(),
+                    placeholder = { Text("Type a command…") },
+                )
+                Spacer(modifier = Modifier.height(8.dp))
+                if (filtered.isEmpty()) {
+                    Text("No matching commands.", fontSize = 12.sp, color = Color(0xFF8A93A6))
+                } else {
+                    filtered.forEach { (id, label) ->
+                        Row(
+                            modifier = Modifier
+                                .fillMaxWidth()
+                                .clip(RoundedCornerShape(6.dp))
+                                .clickable { onAction(id) }
+                                .padding(vertical = 6.dp, horizontal = 4.dp),
+                        ) {
+                            Text(label, fontSize = 13.sp)
+                        }
+                    }
+                }
+            }
+        },
+        confirmButton = {},
+        dismissButton = { TextButton(onClick = onDismiss) { Text("Close") } },
+    )
+}
+
 /** Horizontal topic chips: General + threads + "new topic". */
 @Composable
 private fun TopicSwitcher(
@@ -430,10 +786,12 @@ private fun TopicChip(label: String, selected: Boolean, onClick: () -> Unit) {
     }
 }
 
-/** Full-screen search overlay (M3). */
+/** Full-screen search overlay (M3; M6: all / this-chat scope toggle). */
 @Composable
 private fun SearchOverlay(
     controller: IrisController,
+    currentChatId: String,
+    currentThreadId: String?,
     onJump: (SearchHit) -> Unit,
     onDismiss: () -> Unit,
 ) {
@@ -441,6 +799,15 @@ private fun SearchOverlay(
     val searching by controller.searching.collectAsState()
     val lastQuery by controller.lastQuery.collectAsState()
     var query by remember { mutableStateOf(lastQuery) }
+    var scope by remember { mutableStateOf("all") }
+
+    fun doSearch() {
+        if (scope == "chat") {
+            controller.search(query, scope = "chat", chatId = currentChatId, threadId = currentThreadId)
+        } else {
+            controller.search(query)
+        }
+    }
 
     Box(modifier = Modifier.fillMaxSize().background(Color.Black.copy(alpha = 0.5f))) {
         Column(
@@ -460,13 +827,26 @@ private fun SearchOverlay(
                     modifier = Modifier.weight(1f),
                     placeholder = { Text("Search messages…") },
                     keyboardOptions = KeyboardOptions(imeAction = ImeAction.Search),
-                    keyboardActions = KeyboardActions(onSearch = { controller.search(query) }),
+                    keyboardActions = KeyboardActions(onSearch = { doSearch() }),
                 )
                 Spacer(modifier = Modifier.width(8.dp))
-                Button(onClick = { controller.search(query) }, enabled = query.isNotBlank() && !searching) {
+                Button(onClick = { doSearch() }, enabled = query.isNotBlank() && !searching) {
                     Text(if (searching) "…" else "search")
                 }
             }
+            Row(
+                verticalAlignment = Alignment.CenterVertically,
+                horizontalArrangement = Arrangement.spacedBy(8.dp),
+                modifier = Modifier.padding(top = 4.dp),
+            ) {
+                Text("Scope:", fontSize = 12.sp, color = Color(0xFF8A93A6))
+                TextButton(onClick = { scope = "all" }) {
+                    Text(if (scope == "all") "● all" else "○ all", fontSize = 12.sp)
+                }
+                TextButton(onClick = { scope = "chat" }) {
+                    Text(if (scope == "chat") "● this chat" else "○ this chat", fontSize = 12.sp)
+                }
+            }
             Spacer(modifier = Modifier.height(12.dp))
             if (results.isEmpty() && !searching) {
                 Box(modifier = Modifier.fillMaxSize(), contentAlignment = Alignment.Center) {

app/shared/src/desktopMain/kotlin/iris/platform/DesktopBridge.kt

@@ -0,0 +1,30 @@
+package iris.platform
+
+import iris.state.IrisController
+
+/**
+ * M6: bridge between the desktop shell (tray / window) and the shared
+ * controller. The shell sets [foreground] from the window focus state and
+ * subscribes to [onNotification] for tray updates; [controller] lets the tray
+ * deep-link (notification click -> open chat).
+ */
+typealias NotificationListener =
+    (chatId: String?, title: String, body: String, threadId: String?) -> Unit
+
+object DesktopBridge {
+    @Volatile
+    var foreground: Boolean = true
+
+    @Volatile
+    var controller: IrisController? = null
+
+    private val notificationListeners = mutableListOf<NotificationListener>()
+
+    fun onNotification(listener: NotificationListener) {
+        notificationListeners.add(listener)
+    }
+
+    fun notifyListeners(chatId: String?, title: String, body: String, threadId: String?) {
+        notificationListeners.toList().forEach { it(chatId, title, body, threadId) }
+    }
+}

app/shared/src/desktopMain/kotlin/iris/platform/DesktopMedia.kt

@@ -5,65 +5,92 @@ import androidx.compose.foundation.layout.Column
 import androidx.compose.foundation.layout.Row
 import androidx.compose.foundation.layout.Spacer
 import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.height
 import androidx.compose.foundation.layout.padding
-import androidx.compose.foundation.layout.width
+import androidx.compose.foundation.shape.RoundedCornerShape
+import androidx.compose.foundation.background
+import androidx.compose.foundation.clickable
 import androidx.compose.material3.Button
-import androidx.compose.material3.OutlinedTextField
+import androidx.compose.material3.IconButton
+import androidx.compose.material3.Slider
 import androidx.compose.material3.Text
+import androidx.compose.material3.TextButton
 import androidx.compose.runtime.Composable
+import androidx.compose.runtime.DisposableEffect
+import androidx.compose.runtime.LaunchedEffect
 import androidx.compose.runtime.getValue
 import androidx.compose.runtime.mutableStateOf
 import androidx.compose.runtime.remember
 import androidx.compose.runtime.setValue
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
+import androidx.compose.ui.draw.clip
+import androidx.compose.ui.graphics.Color
 import androidx.compose.ui.graphics.ImageBitmap
-import androidx.compose.ui.graphics.asImageBitmap
+import androidx.compose.ui.graphics.toComposeImageBitmap
 import androidx.compose.ui.unit.dp
 import androidx.compose.ui.unit.sp
 import iris.data.MediaItem
+import java.io.ByteArrayOutputStream
 import java.io.File
+import java.net.StandardProtocolFamily
+import java.net.UnixDomainSocketAddress
+import java.nio.ByteBuffer
+import java.nio.channels.SocketChannel
+import java.util.concurrent.TimeUnit
 import javax.imageio.ImageIO
+import javax.swing.JFileChooser
 import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.delay
 import kotlinx.coroutines.withContext
+import kotlinx.serialization.json.Json
+import kotlinx.serialization.json.JsonArray
+import kotlinx.serialization.json.JsonObject
+import kotlinx.serialization.json.JsonPrimitive
+import kotlinx.serialization.json.buildJsonArray
+import kotlinx.serialization.json.buildJsonObject
+import kotlinx.serialization.json.jsonObject
+import kotlinx.serialization.json.jsonPrimitive
+import kotlin.random.Random
 
+/**
+ * M6: native file dialog (docs/11 §11.2). Runs on the EDT (Compose Desktop's
+ * UI thread), so the chooser is shown directly.
+ */
 @Composable
 actual fun MediaFilePicker(onPicked: (PickedFile?) -> Unit) {
-    var path by remember { mutableStateOf("") }
+    var busy by remember { mutableStateOf(false) }
     Column(
         modifier = Modifier
             .fillMaxWidth()
             .padding(16.dp),
     ) {
-        Text("File path (desktop):", fontSize = 13.sp)
-        Spacer(modifier = Modifier.width(0.dp))
-        OutlinedTextField(
-            value = path,
-            onValueChange = { path = it },
-            modifier = Modifier.fillMaxWidth(),
-            placeholder = { Text("/path/to/file") },
-        )
-        Spacer(modifier = Modifier.width(0.dp))
-        Row {
-            Button(onClick = {
-                val f = File(path.trim())
-                if (f.exists() && f.isFile) {
-                    onPicked(
-                        PickedFile(
+        Text("Attach a file:", fontSize = 13.sp)
+        Spacer(modifier = Modifier.height(8.dp))
+        Button(
+            onClick = {
+                busy = true
+                val picked = pickFile()
+                busy = false
+                onPicked(picked)
+            },
+            enabled = !busy,
+        ) {
+            Text(if (busy) "Choosing…" else "Choose file…")
+        }
+    }
+}
+
+private fun pickFile(): PickedFile? {
+    val chooser = JFileChooser()
+    if (chooser.showOpenDialog(null) != JFileChooser.APPROVE_OPTION) return null
+    val f = chooser.selectedFile ?: return null
+    return PickedFile(
         path = f.absolutePath,
         name = f.name,
         mime = guessMime(f.name),
         size = f.length(),
-                        ),
     )
-                } else {
-                    onPicked(null)
-                }
-            }, enabled = path.isNotBlank()) {
-                Text("Attach")
-            }
-        }
-    }
 }
 
 private fun guessMime(name: String): String {
@@ -73,15 +100,18 @@ private fun guessMime(name: String): String {
         "png" -> "image/png"
         "webp" -> "image/webp"
         "gif" -> "image/gif"
+        "bmp" -> "image/bmp"
         "mp4" -> "video/mp4"
         "webm" -> "video/webm"
         "mov" -> "video/quicktime"
+        "mkv" -> "video/x-matroska"
         "mp3" -> "audio/mpeg"
         "m4a", "aac" -> "audio/mp4"
         "ogg", "opus" -> "audio/ogg"
         "wav" -> "audio/wav"
+        "flac" -> "audio/flac"
         "pdf" -> "application/pdf"
-        "txt" -> "text/plain"
+        "txt", "md" -> "text/plain"
         else -> "application/octet-stream"
     }
 }
@@ -92,24 +122,287 @@ actual fun mediaCacheBaseDir(): String {
     return dir.absolutePath
 }
 
-actual suspend fun loadMediaImage(path: String): ImageBitmap? {
-    // Desktop image decoding via BufferedImage->ImageBitmap is a later
-    // milestone; return null so bubbles show the "loading" placeholder.
-    return null
+actual suspend fun loadMediaImage(path: String): ImageBitmap? = withContext(Dispatchers.IO) {
+    try {
+        val img = ImageIO.read(File(path)) ?: return@withContext null
+        img.toComposeImageBitmap()
+    } catch (_: Exception) {
+        null
+    }
+}
+
+/**
+ * M6: inline media playback backed by mpv (docs/11 §11.2).
+ *
+ * - audio: an mpv process driven over its JSON IPC socket (play/pause/seek,
+ *   position/duration polled every 500 ms) — the same mini-player UX as the
+ *   Android ExoPlayer actual.
+ * - video: mpv in its own window (embedding into a Compose surface would need
+ *   the libmpv JNI renderer; a separate window is the honest v1).
+ * - no mpv on PATH: an info chip (the WebView fallback is a stretch goal).
+ */
+@Composable
+actual fun MediaPlayerView(media: MediaItem, modifier: Modifier) {
+    val path = media.localPath
+    if (path == null || !File(path).exists()) {
+        Box(modifier = modifier.fillMaxWidth(), contentAlignment = Alignment.Center) {
+            Text(
+                "${media.kind}: ${media.filename} (${media.size} B) — not downloaded yet",
+                fontSize = 12.sp,
+            )
+        }
+        return
+    }
+    if (!Mpv.available) {
+        Box(modifier = modifier.fillMaxWidth(), contentAlignment = Alignment.Center) {
+            Text(
+                "${media.kind}: ${media.filename} (${media.size} B) — playback unavailable (mpv not installed)",
+                fontSize = 12.sp,
+            )
+        }
+        return
+    }
+    if (media.kind == "video") VideoPlayer(media, path) else AudioPlayer(media, path)
+}
+
+private object Mpv {
+    val available: Boolean by lazy {
+        try {
+            val p = ProcessBuilder("which", "mpv").redirectErrorStream(true).start()
+            val found = p.inputStream.bufferedReader().readText().trim().isNotBlank()
+            p.waitFor(2, TimeUnit.SECONDS)
+            found
+        } catch (_: Exception) {
+            false
+        }
+    }
 }
 
 @Composable
-actual fun MediaPlayerView(media: MediaItem, modifier: Modifier) {
-    // Desktop playback backend (libmpv/WebView) is a later milestone;
-    // show a chip with the file info for now.
-    Box(modifier = modifier.fillMaxWidth(), contentAlignment = Alignment.Center) {
-        Text(
-            "${media.kind}: ${media.filename} (${media.size} B) — playback not available on desktop yet",
-            fontSize = 12.sp,
+private fun AudioPlayer(media: MediaItem, path: String) {
+    val session = remember(path) { MpvAudioSession(path) }
+    var paused by remember { mutableStateOf(true) }
+    var position by remember { mutableStateOf(0.0) }
+    var duration by remember { mutableStateOf(0.0) }
+    var dragValue by remember { mutableStateOf(0f) }
+
+    DisposableEffect(session) {
+        session.start()
+        onDispose { session.stop() }
+    }
+    LaunchedEffect(session) {
+        while (true) {
+            delay(500)
+            val (p, d, pause) = session.poll()
+            position = p
+            duration = d
+            paused = pause
+        }
+    }
+
+    Column(
+        modifier = Modifier
+            .fillMaxWidth()
+            .clip(RoundedCornerShape(10.dp))
+            .background(Color(0xFF20242E))
+            .padding(10.dp),
+    ) {
+        Text(media.filename, fontSize = 12.sp, maxLines = 1)
+        Spacer(modifier = Modifier.height(6.dp))
+        Row(verticalAlignment = Alignment.CenterVertically) {
+            IconButton(onClick = { session.setPaused(!paused) }) {
+                Text(if (paused) "▶" else "⏸", fontSize = 16.sp)
+            }
+            Slider(
+                value = if (duration > 0) (position / duration).coerceIn(0.0, 1.0).toFloat() else 0f,
+                onValueChange = { dragValue = it },
+                onValueChangeFinished = {
+                    if (duration > 0) session.seekTo(dragValue.toDouble() * duration)
+                },
+                modifier = Modifier.weight(1f),
+                enabled = duration > 0,
             )
+            Text(
+                "${fmtTime(position)} / ${fmtTime(duration)}",
+                fontSize = 11.sp,
+                color = Color(0xFF8A93A6),
+            )
+        }
+    }
+}
+
+@Composable
+private fun VideoPlayer(media: MediaItem, path: String) {
+    var process by remember { mutableStateOf<Process?>(null) }
+    Column(
+        modifier = Modifier
+            .fillMaxWidth()
+            .clip(RoundedCornerShape(10.dp))
+            .background(Color(0xFF20242E))
+            .padding(10.dp),
+    ) {
+        Text(media.filename, fontSize = 12.sp, maxLines = 1)
+        Spacer(modifier = Modifier.height(6.dp))
+        Row(verticalAlignment = Alignment.CenterVertically) {
+            Button(onClick = {
+                try {
+                    process?.destroy()
+                    process = ProcessBuilder("mpv", path).redirectErrorStream(true).start()
+                } catch (_: Exception) {
+                }
+            }) {
+                Text("▶ Play in mpv")
+            }
+            if (process != null) {
+                Spacer(modifier = Modifier.height(0.dp).padding(start = 8.dp))
+                TextButton(onClick = {
+                    process?.destroy()
+                    process = null
+                }) {
+                    Text("stop")
+                }
+            }
+        }
+    }
+}
+
+private fun fmtTime(sec: Double): String {
+    val s = sec.coerceAtLeast(0.0).toLong()
+    return "%d:%02d".format(s / 60, s % 60)
+}
+
+/**
+ * An mpv process + its JSON IPC socket (unix domain). Commands carry a
+ * [requestId] so responses can be matched and async events skipped.
+ */
+private class MpvAudioSession(private val path: String) {
+    private var process: Process? = null
+    private var channel: SocketChannel? = null
+    private val socketPath =
+        "/tmp/iris-mpv-${ProcessHandle.current().pid()}-${Random.nextLong(1_000_000_000L, 9_999_999_999L)}.sock"
+    private val lineBuffer = StringBuilder()
+    private val json = Json { ignoreUnknownKeys = true }
+
+    fun start() {
+        try {
+            process = ProcessBuilder(
+                "mpv", "--no-video", "--really-quiet", "--no-terminal",
+                "--input-ipc-server=$socketPath", path,
+            ).redirectErrorStream(true).start()
+            connectIpc()
+        } catch (_: Exception) {
+        }
+    }
+
+    private fun connectIpc() {
+        repeat(20) {
+            try {
+                val ch = SocketChannel.open(StandardProtocolFamily.UNIX)
+                ch.connect(UnixDomainSocketAddress.of(File(socketPath).toPath()))
+                channel = ch
+                return
+            } catch (_: Exception) {
+                Thread.sleep(150)
+            }
+        }
+    }
+
+    /** Poll time-pos / duration / pause. Returns (position, duration, paused). */
+    fun poll(): Triple<Double, Double, Boolean> {
+        var pos = 0.0
+        var dur = 0.0
+        var pause = false
+        val ch = channel ?: return Triple(pos, dur, pause)
+        try {
+            send(listOf("get_property", "time-pos"), "p1")
+            send(listOf("get_property", "duration"), "p2")
+            send(listOf("get_property", "pause"), "p3")
+            val deadline = System.currentTimeMillis() + 250
+            val answers = mutableMapOf<String, JsonObject>()
+            while (System.currentTimeMillis() < deadline && answers.size < 3) {
+                val line = readLineOrNull() ?: break
+                if (line.isBlank()) continue
+                try {
+                    val el = json.parseToJsonElement(line).jsonObject
+                    val rid = el["request_id"]?.jsonPrimitive?.content
+                    if (rid != null) answers[rid] = el
+                } catch (_: Exception) {
+                }
+            }
+            answers["p1"]?.get("data")?.jsonPrimitive?.content?.toDoubleOrNull()?.let { pos = it }
+            answers["p2"]?.get("data")?.jsonPrimitive?.content?.toDoubleOrNull()?.let { dur = it }
+            answers["p3"]?.get("data")?.jsonPrimitive?.content?.toBooleanStrictOrNull()?.let { pause = it }
+        } catch (_: Exception) {
+        }
+        return Triple(pos, dur, pause)
+    }
+
+    fun setPaused(p: Boolean) {
+        try {
+            send(listOf("set_property", "pause", if (p) "true" else "false"), null)
+        } catch (_: Exception) {
+        }
+    }
+
+    fun seekTo(seconds: Double) {
+        try {
+            send(listOf("seek", seconds.toString(), "absolute"), null)
+        } catch (_: Exception) {
+        }
+    }
+
+    fun stop() {
+        try {
+            channel?.close()
+        } catch (_: Exception) {
+        }
+        process?.destroy()
+        try {
+            File(socketPath).delete()
+        } catch (_: Exception) {
+        }
+    }
+
+    private fun send(cmd: List<String>, requestId: String?) {
+        val ch = channel ?: return
+        val obj = buildJsonObject {
+            put("command", buildJsonArray { cmd.forEach { add(JsonPrimitive(it)) } })
+            requestId?.let { put("request_id", JsonPrimitive(it)) }
+        }
+        val bytes = (obj.toString() + "\n").toByteArray(Charsets.UTF_8)
+        ch.write(ByteBuffer.wrap(bytes))
+    }
+
+    private fun readLineOrNull(): String? {
+        val ch = channel ?: return null
+        val buf = ByteBuffer.allocate(4096)
+        while (true) {
+            val n = ch.read(buf)
+            if (n == -1) return null
+            if (n > 0) break
+            Thread.sleep(20)
+        }
+        buf.flip()
+        val bytes = ByteArray(buf.remaining())
+        buf.get(bytes)
+        lineBuffer.append(String(bytes, Charsets.UTF_8))
+        val idx = lineBuffer.indexOf('\n')
+        if (idx < 0) return null
+        val line = lineBuffer.substring(0, idx)
+        lineBuffer.delete(0, idx + 1)
+        return line
     }
 }
 
 actual fun openDocument(path: String, mime: String) {
-    // Desktop open-with is a later milestone; no-op for now.
+    try {
+        val os = System.getProperty("os.name").lowercase()
+        when {
+            os.contains("mac") -> ProcessBuilder("open", path).start()
+            os.contains("win") ->
+                ProcessBuilder("rundll32", "url.dll,FileProtocolHandler", path).start()
+            else -> ProcessBuilder("xdg-open", path).start()
+        }
+    } catch (_: Exception) {
+    }
 }

app/shared/src/desktopMain/kotlin/iris/platform/DesktopPush.kt

@@ -1,6 +1,8 @@
 package iris.platform
 
-actual fun isAppForeground(): Boolean = true
+import iris.state.IrisController
+
+actual fun isAppForeground(): Boolean = DesktopBridge.foreground
 
 actual fun postSystemNotification(
     chatId: String?,
@@ -9,9 +11,49 @@ actual fun postSystemNotification(
     body: String,
     threadId: String?,
 ) {
-    // Desktop: in-app banner only (no system notification in M5).
+    DesktopNotifier.post(title, body)
+    DesktopBridge.notifyListeners(chatId, title, body, threadId)
 }
 
 actual fun setActiveController(controller: Any?) {
-    // Desktop: no push services to bridge to.
+    DesktopBridge.controller = controller as? IrisController
+}
+
+/**
+ * M6: OS notifications (docs/11 §11.2). Desktop has no FCM; the tray + the
+ * platform notifier cover the "backgrounded" leg. Shells out to
+ * notify-send (Linux), osascript (macOS) or a PowerShell balloon (Windows).
+ * Best effort — failures are ignored (the in-app banner is the primary path).
+ */
+object DesktopNotifier {
+    fun post(title: String, body: String) {
+        try {
+            val os = System.getProperty("os.name").lowercase()
+            val cmd = when {
+                os.contains("linux") ->
+                    listOf("notify-send", "-a", "Iris", "-c", "iris", title, body)
+                os.contains("mac") ->
+                    listOf(
+                        "osascript", "-e",
+                        "display notification \"${esc(body)}\" with title \"${esc(title)}\"",
+                    )
+                else ->
+                    listOf(
+                        "powershell", "-NoProfile", "-Command",
+                        "Add-Type -AssemblyName System.Windows.Forms; " +
+                            "\$n = New-Object System.Windows.Forms.NotifyIcon; " +
+                            "\$n.Icon = [System.Drawing.SystemIcons]::Information; " +
+                            "\$n.Visible = \$true; " +
+                            "\$n.ShowBalloonTip(4000, \"${esc(title)}\", \"${esc(body)}\", " +
+                            "[System.Windows.Forms.ToolTipIcon]::Info); " +
+                            "Start-Sleep -Milliseconds 4500; \$n.Dispose()",
+                    )
+            }
+            ProcessBuilder(cmd).redirectErrorStream(true).start()
+        } catch (_: Exception) {
+        }
+    }
+
+    private fun esc(s: String): String =
+        s.replace("\\", "\\\\").replace("\"", "\\\"").replace("\n", " ")
 }

app/shared/src/desktopMain/kotlin/iris/platform/DesktopSecureStore.kt

@@ -3,42 +3,81 @@ package iris.platform
 import iris.data.SecureStore
 import iris.protocol.IrisJson
 import java.io.File
+import java.security.SecureRandom
 import java.util.UUID
+import javax.crypto.Cipher
+import javax.crypto.spec.GCMParameterSpec
+import javax.crypto.spec.SecretKeySpec
 import kotlinx.serialization.Serializable
 
 /**
- * Desktop pairing storage: a small JSON file under the user home
- * (`~/.iris/pairing.json`). M1 dev storage; a keyring backend is a
- * later-milestone concern.
+ * M6: desktop pairing storage (docs/11 §11.2).
+ *
+ * Non-secret settings live in `~/.iris/settings.json`; the gateway token goes
+ * to the OS keyring (macOS Keychain via `security`, Linux Secret Service via
+ * `secret-tool`) when available, falling back to an AES-GCM encrypted file
+ * (`~/.iris/pairing.enc`, key in `~/.iris/.key`, owner-only permissions).
+ *
+ * Migrates the M1 plaintext `~/.iris/pairing.json` on first run.
  */
-@Serializable
-private data class PairingData(
+class DesktopSecureStore : SecureStore {
+    private val baseDir = File(System.getProperty("user.home"), ".iris")
+    private val settingsFile = File(baseDir, "settings.json")
+    private val legacyFile = File(baseDir, "pairing.json")
+    private val secret = SecretBackend(baseDir)
+
+    @Serializable
+    private data class Settings(
         val serverUrl: String = "",
-    val token: String = "",
         val deviceId: String = "",
         val syncCursor: Long = 0L,
         val fcmToken: String = "",
         val ntfyTopic: String = "",
         val ntfyServer: String = "",
-)
+    )
 
-class DesktopSecureStore : SecureStore {
-    private val file: File = File(System.getProperty("user.home"), ".iris/pairing.json")
+    init {
+        migrateLegacy()
+    }
 
-    private fun load(): PairingData =
-        if (file.exists()) {
-            try {
-                IrisJson.instance.decodeFromString(PairingData.serializer(), file.readText())
+    private fun migrateLegacy() {
+        if (!legacyFile.exists()) return
+        val legacy = try {
+            IrisJson.instance.decodeFromString(PairingData.serializer(), legacyFile.readText())
         } catch (_: Exception) {
-                PairingData()
+            null
+        }
+        if (legacy != null) {
+            val s = load()
+            save(
+                s.copy(
+                    serverUrl = legacy.serverUrl.ifBlank { s.serverUrl },
+                    deviceId = legacy.deviceId.ifBlank { s.deviceId },
+                    syncCursor = if (legacy.syncCursor > 0) legacy.syncCursor else s.syncCursor,
+                    fcmToken = legacy.fcmToken.ifBlank { s.fcmToken },
+                    ntfyTopic = legacy.ntfyTopic.ifBlank { s.ntfyTopic },
+                    ntfyServer = legacy.ntfyServer.ifBlank { s.ntfyServer },
+                ),
+            )
+            if (legacy.token.isNotBlank()) secret.write(legacy.token)
+        }
+        legacyFile.delete()
+    }
+
+    private fun load(): Settings =
+        if (settingsFile.exists()) {
+            try {
+                IrisJson.instance.decodeFromString(Settings.serializer(), settingsFile.readText())
+            } catch (_: Exception) {
+                Settings()
             }
         } else {
-            PairingData()
+            Settings()
         }
 
-    private fun save(data: PairingData) {
-        file.parentFile?.mkdirs()
-        file.writeText(IrisJson.instance.encodeToString(PairingData.serializer(), data))
+    private fun save(data: Settings) {
+        baseDir.mkdirs()
+        settingsFile.writeText(IrisJson.instance.encodeToString(Settings.serializer(), data))
     }
 
     override var serverUrl: String
@@ -49,10 +88,9 @@ class DesktopSecureStore : SecureStore {
         }
 
     override var token: String
-        get() = load().token
+        get() = secret.read().orEmpty()
         set(value) {
-            val d = load()
-            save(d.copy(token = value.trim()))
+            if (value.isBlank()) secret.clear() else secret.write(value.trim())
         }
 
     override val deviceId: String
@@ -97,11 +135,169 @@ class DesktopSecureStore : SecureStore {
 
     override fun savePairing(url: String, token: String) {
         val d = load()
-        save(d.copy(serverUrl = url.trim(), token = token.trim()))
+        save(d.copy(serverUrl = url.trim()))
+        if (token.isBlank()) secret.clear() else secret.write(token.trim())
     }
 
     override fun clear() {
         val d = load()
-        save(d.copy(serverUrl = "", token = ""))
+        save(d.copy(serverUrl = ""))
+        secret.clear()
+    }
+}
+
+/** Legacy M1 shape, kept only for migration. */
+@Serializable
+private data class PairingData(
+    val serverUrl: String = "",
+    val token: String = "",
+    val deviceId: String = "",
+    val syncCursor: Long = 0L,
+    val fcmToken: String = "",
+    val ntfyTopic: String = "",
+    val ntfyServer: String = "",
+)
+
+/**
+ * Token storage: OS keyring when available, else an AES-GCM encrypted file.
+ * All backend failures degrade to the encrypted file (never plaintext).
+ */
+private class SecretBackend(private val baseDir: File) {
+    private val encFile = File(baseDir, "pairing.enc")
+    private val keyFile = File(baseDir, ".key")
+    private val keyring: KeyringBackend? = KeyringBackend().takeIf { it.available }
+
+    fun read(): String? = keyring?.read() ?: readEncrypted()
+
+    fun write(value: String) {
+        if (keyring != null) {
+            keyring.write(value)
+            if (keyring.read() == value) return
+            // Keyring accepted the write but did not persist it (e.g. KWallet
+            // without a live daemon). Drop the stale entry and fall back to
+            // the encrypted file so the token survives a restart.
+            keyring.clear()
+        }
+        writeEncrypted(value)
+    }
+
+    fun clear() {
+        keyring?.clear()
+        encFile.delete()
+    }
+
+    private fun loadKey(): ByteArray {
+        if (keyFile.exists()) return keyFile.readBytes()
+        val key = ByteArray(32).also { SecureRandom().nextBytes(it) }
+        baseDir.mkdirs()
+        keyFile.writeBytes(key)
+        try {
+            keyFile.setReadable(false, false)
+            keyFile.setWritable(false, false)
+            keyFile.setReadable(true, true)
+            keyFile.setWritable(true, true)
+        } catch (_: Exception) {
+        }
+        return key
+    }
+
+    private fun writeEncrypted(value: String) {
+        try {
+            val cipher = Cipher.getInstance("AES/GCM/NoPadding")
+            val iv = ByteArray(12).also { SecureRandom().nextBytes(it) }
+            cipher.init(Cipher.ENCRYPT_MODE, SecretKeySpec(loadKey(), "AES"), GCMParameterSpec(128, iv))
+            val ct = cipher.doFinal(value.toByteArray(Charsets.UTF_8))
+            baseDir.mkdirs()
+            encFile.writeBytes(iv + ct)
+        } catch (_: Exception) {
+        }
+    }
+
+    private fun readEncrypted(): String? {
+        if (!encFile.exists()) return null
+        return try {
+            val bytes = encFile.readBytes()
+            if (bytes.size < 28) return null
+            val iv = bytes.copyOfRange(0, 12)
+            val ct = bytes.copyOfRange(12, bytes.size)
+            val cipher = Cipher.getInstance("AES/GCM/NoPadding")
+            cipher.init(Cipher.DECRYPT_MODE, SecretKeySpec(loadKey(), "AES"), GCMParameterSpec(128, iv))
+            String(cipher.doFinal(ct), Charsets.UTF_8)
+        } catch (_: Exception) {
+            null
+        }
+    }
+}
+
+/** OS keyring via the platform CLI (best effort). */
+private class KeyringBackend {
+    private val os = System.getProperty("os.name").lowercase()
+    private val isMac = os.contains("mac")
+    private val isLinux = os.contains("linux")
+
+    /** macOS Keychain (`security`) or Linux Secret Service (`secret-tool`). */
+    val available: Boolean by lazy {
+        if (isMac) true
+        else if (isLinux) which("secret-tool") != null
+        else false
+    }
+
+    fun read(): String? = try {
+        if (isMac) {
+            out(listOf("security", "find-generic-password", "-a", "iris", "-s", "iris-gateway-token", "-w"))
+        } else {
+            out(listOf("secret-tool", "lookup", "app", "iris"))
+        }
+    } catch (_: Exception) {
+        null
+    }
+
+    fun write(value: String) {
+        try {
+            if (isMac) {
+                ProcessBuilder(
+                    "security", "add-generic-password", "-U",
+                    "-a", "iris", "-s", "iris-gateway-token", "-w", value,
+                ).inheritIO().start().waitFor()
+            } else {
+                ProcessBuilder(
+                    "secret-tool", "store", "--label=Iris gateway token",
+                    "app", "iris", "token", value,
+                ).inheritIO().start().waitFor()
+            }
+        } catch (_: Exception) {
+        }
+    }
+
+    fun clear() {
+        try {
+            if (isMac) {
+                ProcessBuilder(
+                    "security", "delete-generic-password",
+                    "-a", "iris", "-s", "iris-gateway-token",
+                ).inheritIO().start().waitFor()
+            } else {
+                ProcessBuilder(
+                    "secret-tool", "clear", "app", "iris",
+                ).inheritIO().start().waitFor()
+            }
+        } catch (_: Exception) {
+        }
+    }
+
+    private fun out(cmd: List<String>): String? {
+        val p = ProcessBuilder(cmd).redirectErrorStream(true).start()
+        val text = p.inputStream.bufferedReader().readText().trim()
+        p.waitFor()
+        return text.ifBlank { null }
+    }
+
+    private fun which(bin: String): String? = try {
+        val p = ProcessBuilder("which", bin).redirectErrorStream(true).start()
+        val text = p.inputStream.bufferedReader().readText().trim()
+        p.waitFor()
+        text.ifBlank { null }
+    } catch (_: Exception) {
+        null
     }
 }

app/shared/src/desktopMain/kotlin/iris/platform/Platform.kt

@@ -0,0 +1,3 @@
+package iris.platform
+
+actual val isDesktop: Boolean = true

docs/14-milestones.md

@@ -144,15 +144,38 @@ has explicit **acceptance criteria**. Work top-to-bottom; don't skip M0/M1.
 
 ## M6 — Desktop app
 **Goal:** the same app on a big screen.
-- [ ] `desktopMain`: tray + OS notifications; `MediaPlayer` actual (mpv/WebView);
+- [x] `desktopMain`: tray + OS notifications; `MediaPlayer` actual (mpv/WebView);
       `MediaPicker` actual (file dialog); `SecureStore` actual; window mgmt.
-- [ ] Two-pane default layout; keyboard shortcuts; optional inspector pane.
+- [x] Two-pane default layout; keyboard shortcuts; optional inspector pane.
 - [ ] Parity pass vs Android feature checklist (`11-desktop-app.md`).
-- [ ] jpackage builds (Linux first; macOS/Windows as available).
+- [x] jpackage builds (Linux first; macOS/Windows as available).
 - **Demo:** desktop app pairs to the same gateway; full feature parity; tray
   notifications; media plays.
 - **Accept:** all Android features work on desktop; tray + shortcuts work;
   native binary launches.
+- **Status (complete, 2026-08-19):** All `desktopMain` actuals implemented and
+  verified on Linux (X11). `DesktopSecureStore`: non-secrets in
+  `~/.iris/settings.json`; the gateway token goes to the OS keyring with
+  read-back verification, falling back to an AES-GCM encrypted file
+  (`~/.iris/pairing.enc` + owner-only `~/.iris/.key`) when the keyring doesn't
+  persist — KWallet on this host accepts writes without storing, so the
+  fallback is exercised (a stale keyring entry is cleared before falling back).
+  `DesktopMedia`: `JFileChooser` picker, ImageIO thumbnails, mpv playback
+  (audio via a JSON-IPC unix socket, video in a separate mpv window), docs via
+  `xdg-open`. `DesktopPush`: `notify-send` OS notifications + in-app banners,
+  foreground-aware via window focus (`DesktopBridge.foreground`). Tray (Compose
+  `Tray`): connection-state icon + tooltip, Show/Quit menu, close-to-tray.
+  Window size/position persisted to `~/.iris/window.json`. Two-pane layout
+  (channel rail + chat) + optional inspector pane + keyboard shortcuts
+  (Ctrl/Cmd N/T/F/K, Esc, `/` command palette) + search scope toggle.
+  Verified on-device: the app pairs to the same gateway, connects (green
+  "connected" chip), renders the two-pane layout, and replays the outbox.
+  jpackage Linux app-image builds (`./gradlew :desktopApp:jpackage`) and the
+  native binary launches + connects. Known: the jpackage launcher prints a
+  non-fatal "pure virtual method called" (JDK-8348560, a jpackage/Linux
+  launcher bug on JDK 17; the app runs and connects regardless). Parity is
+  achieved via shared-code reuse; a formal feature-by-feature parity pass and
+  macOS/Windows packaging are deferred to M7.
 
 ## M7 — Polish + E2E + docs
 **Goal:** ship-quality.