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

app/Models/Subscription.php

@@ -65,6 +65,8 @@ class Subscription extends Model
         'amount',
         'currency',
         'expires_at',
+        'uncanceled_at',
+        'cancel_at_period_end',
     ];
 
     protected $casts = [