Description

Add Android home screen widget showing pending updates count with quick update action.

Current Behavior

• No home screen widget available
• Must open app to see update status
• No quick action from home screen

Proposed Changes

1. Create simple 1x1 widget showing pending updates count
2. Create 2x2 widget showing:
   • Pending updates count
   • "Update All" button
   • Last check time
3. Create 4x1 widget showing list of apps with updates
4. Tap to open Obtainium+ app
5. Auto-refresh widget when updates checked

Priority

Low - Convenience feature

Files Affected

• New: android/app/src/main/java/.../widget/
• android/app/src/main/AndroidManifest.xml
• New: lib/services/widget_service.dart