feat(notifications): implement comprehensive telegram notifications for payment providers
- Add NotifyMe trait with centralized Telegram bot integration
- Implement webhook notifications for Polar, OxaPay, and ActivationKey providers
- Add subscription lifecycle notifications (create, activate, cancel, pause, resume)
- Enhance Polar webhook processing with user context and error handling
- Fix subscription.updated and subscription.canceled webhook column errors
- Add idempotent webhook processing to prevent duplicate handling
0d33c57b32