- Add PendingIntentManager class for proper PendingIntent handling
- Implement correct FLAG_UPDATE_CURRENT | FLAG_IMMUTABLE flags for Android 12+
- Add comprehensive exact alarm permission checking and handling
- Add fallback to windowed alarms when exact alarm permission denied
- Update DailyNotificationScheduler to use PendingIntentManager
- Add detailed alarm status reporting with Android version info
- Improve error handling for SecurityException on exact alarm scheduling
- Add comprehensive alarm status to checkStatus() method
P0 Priority Implementation:
- Fixes PendingIntent flags for modern Android compatibility
- Ensures exact alarm permissions are properly checked before scheduling
- Provides actionable error messages when exact alarm permission denied
- Adds fallback to windowed alarms for better reliability
- Improves alarm scheduling status reporting and debugging
This addresses the critical P0 issues with PendingIntent flags and
exact alarm permission handling for production reliability.