- Add complete iOS plugin implementation with BGTaskScheduler integration
- Implement Core Data model mirroring Android SQLite schema (ContentCache, Schedule, Callback, History)
- Add background task handlers for content fetch and notification delivery
- Implement TTL-at-fire logic with Core Data persistence
- Add callback management with HTTP and local callback support
- Include comprehensive error handling and structured logging
- Add Info.plist configuration for background tasks and permissions
- Support for dual scheduling with BGAppRefreshTask and BGProcessingTask
BREAKING CHANGE: iOS implementation requires iOS 13.0+ and background task permissions