feat: add APNs push notification support

- Add push package (3.3.3) for native iOS push without Firebase
- Add Runner.entitlements with aps-environment=development
- Wire CODE_SIGN_ENTITLEMENTS in all three build configs (Debug/Release/Profile)
- Update AppDelegate.swift to forward UNUserNotificationCenter delegate methods
- Add remote-notification to UIBackgroundModes in Info.plist
- Add PushService: requests permission, listens for tokens, sends to daemon
  via MQTT on pailot/device/token, handles notification tap for session routing
- Add MqttService.sendDeviceToken(): publishes token to pailot/device/token
- Initialize PushService after MQTT connect in chat_screen.dart
- Re-register token on MQTT reconnect so daemon always has fresh token

	ios/Podfile.lock	diff | view | blame | history
	ios/Runner.xcodeproj/project.pbxproj	diff | view | blame | history
	ios/Runner/AppDelegate.swift	diff | view | blame | history
	ios/Runner/Info.plist	diff | view | blame | history
	ios/Runner/Runner.entitlements	diff | view | blame | history
	lib/screens/chat_screen.dart	diff | view | blame | history
	lib/services/mqtt_service.dart	diff | view | blame | history
	lib/services/push_service.dart	diff | view | blame | history
	macos/Flutter/GeneratedPluginRegistrant.swift	diff | view | blame | history
	pubspec.lock	diff | view | blame | history
	pubspec.yaml	diff | view | blame | history