merge: integrate upstream RPG attributes customization system

Merged commits from upstream/main (d870731):
- Add customizable RPG attributes (STR/DEX/etc) with add/remove/rename
- Fix character stats editing (0% display bug, missing Stats line creation)
- Add mobile font-size overrides for better readability
- Fix together mode rendering order (render panels before cleaning DOM)
- Fix temperature unit toggle (C/F) and thermometer thresholds
- Add buildAttributesString() for custom attribute names in AI prompts

Upstream Features:
- trackerConfig.rpgAttributes array replaces showRPGAttributes boolean
- Per-attribute enable/disable, custom names, reordering
- Tracker editor UI for managing attributes
- Custom attribute names appear in AI prompts and dice rolls
- Backward compatible migration from old boolean toggle

Merge Conflict Resolution:
- src/systems/integration/sillytavern.js:
  * Kept both: upstream's "render before DOM cleaning" + our refreshDashboard()
  * Result: render panels → refresh dashboard → update DOM
- style.css:
  * Kept both: our Widget Integration CSS + upstream's Mobile Font Overrides
  * Our Recent Events width fix (width: 100%) preserved

Related upstream commits:
- d870731: Add customizable RPG attributes and fix character stats editing
- f20710f: Make RPG attributes customizable and editable
- 883212b: Add comprehensive mobile font-size overrides
- 718696e: Fix multiple UI and functionality issues

No functional changes to v2 dashboard yet - integration in next commit.

src/core/persistence.js

@@ -381,6 +381,14 @@ function migrateToTrackerConfig() {
             userStats: {
                 customStats: [],
                 showRPGAttributes: true,
+                rpgAttributes: [
+                    { id: 'str', name: 'STR', enabled: true },
+                    { id: 'dex', name: 'DEX', enabled: true },
+                    { id: 'con', name: 'CON', enabled: true },
+                    { id: 'int', name: 'INT', enabled: true },
+                    { id: 'wis', name: 'WIS', enabled: true },
+                    { id: 'cha', name: 'CHA', enabled: true }
+                ],
                 statusSection: {
                     enabled: true,
                     showMoodEmoji: true,
@@ -438,6 +446,47 @@ function migrateToTrackerConfig() {
         }
     }
 
+    // Migrate old showRPGAttributes boolean to rpgAttributes array
+    if (extensionSettings.trackerConfig.userStats.showRPGAttributes !== undefined) {
+        const shouldShow = extensionSettings.trackerConfig.userStats.showRPGAttributes;
+        extensionSettings.trackerConfig.userStats.rpgAttributes = [
+            { id: 'str', name: 'STR', enabled: shouldShow },
+            { id: 'dex', name: 'DEX', enabled: shouldShow },
+            { id: 'con', name: 'CON', enabled: shouldShow },
+            { id: 'int', name: 'INT', enabled: shouldShow },
+            { id: 'wis', name: 'WIS', enabled: shouldShow },
+            { id: 'cha', name: 'CHA', enabled: shouldShow }
+        ];
+        delete extensionSettings.trackerConfig.userStats.showRPGAttributes;
+        console.log('[RPG Companion] Migrated showRPGAttributes to rpgAttributes array');
+    }
+
+    // Ensure rpgAttributes exists even if no migration was needed
+    if (!extensionSettings.trackerConfig.userStats.rpgAttributes) {
+        extensionSettings.trackerConfig.userStats.rpgAttributes = [
+            { id: 'str', name: 'STR', enabled: true },
+            { id: 'dex', name: 'DEX', enabled: true },
+            { id: 'con', name: 'CON', enabled: true },
+            { id: 'int', name: 'INT', enabled: true },
+            { id: 'wis', name: 'WIS', enabled: true },
+            { id: 'cha', name: 'CHA', enabled: true }
+        ];
+    }
+
+    // Ensure showRPGAttributes exists (defaults to true)
+    if (extensionSettings.trackerConfig.userStats.showRPGAttributes === undefined) {
+        extensionSettings.trackerConfig.userStats.showRPGAttributes = true;
+    }
+
+    // Ensure all rpgAttributes have corresponding values in classicStats
+    if (extensionSettings.classicStats) {
+        for (const attr of extensionSettings.trackerConfig.userStats.rpgAttributes) {
+            if (extensionSettings.classicStats[attr.id] === undefined) {
+                extensionSettings.classicStats[attr.id] = 10;
+            }
+        }
+    }
+
     // Migrate old presentCharacters structure to new format
     if (extensionSettings.trackerConfig.presentCharacters) {
         const pc = extensionSettings.trackerConfig.presentCharacters;