- Add manifest.json for proper PWA installation
- Add service worker (sw.js) for push notification handling
- Add ServiceWorkerProvider to register SW and manage notifications
- Generate PNG icons (192x192, 512x512) for iOS compatibility
- Update settings to show notification status and test button
- Use service worker showNotification for iOS Safari compatibility
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
