feat: add Dashboard tab with live GPU overview

Add a new Dashboard tab as the default/first tab (Dashboard - Curve -
Performance - Fans) showing a full GPU overview.

Backend:
- New hal/dashboard.py: one-shot static GPU info via NVML (VBIOS, CUDA
  cores, compute capability, bus width, BAR1/CPU-accessible VRAM,
  Resizable BAR, PCIe max, max clocks, power limits, temp thresholds,
  persistence mode, fan count, serial, board part number, UUID).
  ROP count and VRAM type are best-effort from a per-model table since
  NVML does not expose them.
- New /api/dashboard endpoint.
- MonitoringSample gains live throttle_reasons (+label), PCIe link
  width/generation (downclocks when idle, so read per poll), and VRAM
  temp (from the MEMORY thermal sensor, if exposed).

Frontend:
- New Dashboard component: critical top row (throttling, voltage,
  GPU/VRAM temps), full live-monitor grid with sparklines, and a static
  GPU-information grid. Unavailable fields are omitted.
- useDashboard hook + DashboardInfo type + api.client dashboard().

Also: restrict CORS to localhost origins (end-anchored), make
_int_key_deltas fail closed on bad keys, and clean up lint blockers in
server.py/monitoring.py.

frontend/src/App.tsx

@@ -1,8 +1,10 @@
 import { useGpu } from "./hooks/useGpu";
 import { useCurve } from "./hooks/useCurve";
 import { useMonitor } from "./hooks/useMonitor";
+import { useDashboard } from "./hooks/useDashboard";
 import { StatusBar } from "./components/Monitor/StatusBar";
 import { LiveMonitor } from "./components/Monitor/LiveMonitor";
+import { Dashboard } from "./components/Dashboard/Dashboard";
 import { CurveEditor } from "./components/CurveEditor/CurveEditor";
 import { PointTable } from "./components/PointTable/PointTable";
 import { PerformancePanel } from "./components/Limits/PerformancePanel";
@@ -89,12 +91,13 @@ function MainApp({
   const gpuInfo = useGpu();
   const { curve, wsStatus: curveWsStatus } = useCurve();
   const { monitor, monitorHistory, wsStatus: monitorWsStatus } = useMonitor();
+  const { dashboard, loading: dashboardLoading } = useDashboard();
   const { setCurve, activeProfile, setActiveProfile, selectedGpuIndex } =
     useCurveStore();
 
-  const [activeTab, setActiveTab] = useState<"curve" | "performance" | "fans">(
-    "curve",
-  );
+  const [activeTab, setActiveTab] = useState<
+    "dashboard" | "curve" | "performance" | "fans"
+  >("dashboard");
   const [fanState, setFanState] = useState<FanState | null>(null);
   const [activeDomain, setActiveDomain] = useState<"gpu" | "memory">("gpu");
   const [isProfileOpen, setIsProfileOpen] = useState(false);
@@ -168,6 +171,12 @@ function MainApp({
         {/* Tab Header and Profile Selector */}
         <div className="flex justify-between items-end border-b border-zinc-800 pb-2">
           <div className="flex gap-6">
+            <button
+              onClick={() => setActiveTab("dashboard")}
+              className={`text-lg font-medium pb-2 -mb-[9px] border-b-2 transition-colors ${activeTab === "dashboard" ? "border-pink-500 text-zinc-100" : "border-transparent text-zinc-500 hover:text-zinc-300"}`}
+            >
+              Dashboard
+            </button>
             <button
               onClick={() => setActiveTab("curve")}
               className={`text-lg font-medium pb-2 -mb-[9px] border-b-2 transition-colors ${activeTab === "curve" ? "border-pink-500 text-zinc-100" : "border-transparent text-zinc-500 hover:text-zinc-300"}`}
@@ -222,7 +231,14 @@ function MainApp({
 
         {/* Main content area */}
         <div className="flex flex-col gap-4 w-full">
-          {activeTab === "curve" ? (
+          {activeTab === "dashboard" ? (
+            <Dashboard
+              monitor={monitor}
+              history={monitorHistory}
+              dashboard={dashboard}
+              loading={dashboardLoading}
+            />
+          ) : activeTab === "curve" ? (
             <>
               <div className="flex gap-4 items-stretch w-full">
                 <div className="flex-1 min-w-0 flex flex-col">