feat: add subscription and transaction repositories

- Implemented SubscriptionRepository with methods to get, create, and update subscriptions.
- Added BalanceTXRepository for creating and retrieving balance transactions.
- Introduced a test script for simulating Pally webhook for local testing.

schemas/di.py

@@ -4,6 +4,7 @@ from remnawave import RemnawaveSDK
 
 from misc.pally import PallyClient
 from repositories.bills import BillsRepository
+from repositories.subscriptions import SubscriptionRepository
 from repositories.users import UserRepository
 from services.billing_service import BillingService
 from services.user_service import UserService
@@ -13,10 +14,11 @@ from services.user_service import UserService
 class DependenciesDTO:
     user_repository: UserRepository
     user_service: UserService
-    rw_sdk: RemnawaveSDK
     bills_repository: BillsRepository
     billing_service: BillingService
+    subscriptions_repository: SubscriptionRepository
     pally_client: PallyClient
+    rw_sdk: RemnawaveSDK
 
 
 @dataclass