fix: WebSocket dead-connection recovery, notification delivery, theme system overhaul

- Detect silent WebSocket drops via 30s no-message timeout + 15s heartbeat
- Force reconnect in onAppBackground via foreground service context
- Reduce KeepAlive interval from 15min to 5min for faster background recovery
- Replace callback-based notification with direct NotificationHelper injection
- Suppress notifications during initial launch and when app is foregrounded
- 9 theme color presets (pink default) + Monet dynamic color (Android 12+)
- Full HSL-derived MD3 ColorScheme replacing stale purple-only scheme
- Inline markdown rendering for chat messages (bold, italic, code, links)
- Long-press copy on error/system messages
- Hidden root keep-alive toggle (5-tap) with system-level commands
- BootReceiver to reapply keep-alive and restart service on boot

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

app/src/main/AndroidManifest.xml

@@ -22,6 +22,12 @@
     <!-- 锁屏交互 -->
     <uses-permission android:name="android.permission.USE_FULL_SCREEN_INTENT" />
 
+    <!-- 激进保活 -->
+    <uses-permission android:name="android.permission.WAKE_LOCK" />
+    <uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED" />
+    <uses-permission android:name="android.permission.SCHEDULE_EXACT_ALARM" />
+    <uses-permission android:name="android.permission.REQUEST_IGNORE_BATTERY_OPTIMIZATIONS" />
+
     <!-- 查询其他应用（检查默认助手设置） -->
     <queries>
         <intent>
@@ -89,7 +95,25 @@
         <service
             android:name=".service.WebSocketKeepAliveService"
             android:exported="false"
-            android:foregroundServiceType="dataSync" />
+            android:foregroundServiceType="dataSync|specialUse">
+            <property
+                android:name="android.app.PROPERTY_SPECIAL_USE_FGS_SUBTYPE"
+                android:value="websocket_keepalive_for_push_message_delivery" />
+        </service>
+
+        <!-- 开机自启 -->
+        <receiver
+            android:name=".service.BootReceiver"
+            android:exported="false">
+            <intent-filter>
+                <action android:name="android.intent.action.BOOT_COMPLETED" />
+            </intent-filter>
+        </receiver>
+
+        <!-- 定时保活唤醒 -->
+        <receiver
+            android:name=".service.KeepAliveReceiver"
+            android:exported="false" />
 
         <!-- FileProvider：日志分享 -->
         <provider