Refactor notification handling and streamline router registration

- Replaced legacy notification functions with a unified NotificationService for better maintainability and clarity.
- Updated the main bot router registration to utilize a root router, simplifying the inclusion of user and admin routes.
- Removed unused middleware and helper functions to enhance code cleanliness and focus on essential components.
- Improved localization by adding new error messages for user interactions.

db/dal/payment_dal.py

@@ -47,6 +47,38 @@ async def get_payment_by_provider_payment_id(
     return result.scalar_one_or_none()
 
 
+async def ensure_payment_with_provider_id(
+        session: AsyncSession,
+        *,
+        user_id: int,
+        amount: float,
+        currency: str,
+        months: int,
+        description: str,
+        provider: str,
+        provider_payment_id: str) -> Payment:
+    """Idempotently create a payment record for a provider event.
+
+    If a payment with the same provider_payment_id already exists, returns it.
+    Otherwise creates a new succeeded payment with provided data.
+    """
+    existing = await get_payment_by_provider_payment_id(session, provider_payment_id)
+    if existing:
+        return existing
+
+    payment_payload: Dict[str, Any] = {
+        "user_id": user_id,
+        "amount": float(amount),
+        "currency": currency,
+        "status": "succeeded",
+        "description": description,
+        "subscription_duration_months": months,
+        "provider_payment_id": provider_payment_id,
+        "provider": provider,
+    }
+    return await create_payment_record(session, payment_payload)
+
+
 async def get_payment_by_db_id(session: AsyncSession,
                                payment_db_id: int) -> Optional[Payment]:
 

db/dal/subscription_dal.py

@@ -53,6 +53,29 @@ async def update_subscription(
     return sub
 
 
+async def set_user_subscriptions_cancelled_with_grace(
+        session: AsyncSession, user_id: int, grace_days: int = 1) -> int:
+    """Mark all active user subscriptions as cancelled with a short grace period.
+
+    Sets end_date to now + grace_days, status_from_panel to 'CANCELLED', and
+    skip future notifications to reduce noise after cancellation.
+    Returns number of updated rows.
+    """
+    from datetime import datetime, timezone, timedelta
+    grace_end = datetime.now(timezone.utc) + timedelta(days=grace_days)
+    stmt = (
+        update(Subscription)
+        .where(Subscription.user_id == user_id, Subscription.is_active == True)
+        .values(
+            end_date=grace_end,
+            status_from_panel="CANCELLED",
+            skip_notifications=True,
+        )
+    )
+    result = await session.execute(stmt)
+    return result.rowcount or 0
+
+
 async def upsert_subscription(session: AsyncSession,
                               sub_payload: Dict[str, Any]) -> Subscription:
     panel_sub_uuid = sub_payload.get("panel_subscription_uuid")

db/dal/user_dal.py

@@ -30,20 +30,7 @@ async def get_user_by_panel_uuid(
     return result.scalar_one_or_none()
 
 
-async def get_user(
-    session: AsyncSession,
-    *,
-    user_id: Optional[int] = None,
-    username: Optional[str] = None,
-    panel_uuid: Optional[str] = None,
-) -> Optional[User]:
-    if user_id is not None:
-        return await get_user_by_id(session, user_id)
-    if username is not None:
-        return await get_user_by_username(session, username)
-    if panel_uuid is not None:
-        return await get_user_by_panel_uuid(session, panel_uuid)
-    return None
+## Removed unused generic get_user helper to keep DAL explicit and simple
 
 
 async def create_user(session: AsyncSession, user_data: Dict[str, Any]) -> User: