Add referral system and user balance tracking

Introduce balance field to User model with Alembic migration. Add
referral menu, admin /refpay command, and deep link sharing. Update
Dockerfile to multi-stage build and add Postgres service to compose.
Fix deep link parsing logic and conditional proxy initialization.

services/user_service.py

@@ -49,7 +49,7 @@ class UserService:
 
     @staticmethod
     async def format_admin_support_message(
-        ticket_number: int, user: User, rw_user: Optional[RWUserInfo]
+        ticket_number: int, user: User, rw_user: Optional[RWUserInfo], balance: int
     ):
         username_display = utils.format_username(user.username)
 
@@ -76,6 +76,7 @@ class UserService:
             full_name=user.full_name,
             username_display=username_display,
             telegram_id=user.id,
+            balance=balance,
             status_icon=status_icon,
             status=status_text,
             expire_date=expire_date,
@@ -98,8 +99,10 @@ class UserService:
             return user
 
         rw_user = await get_user_by_telegram_id(rw_sdk, user_id)
-        link = utils.get_subscription_link(rw_user.short_uuid)
-        referal = int(referal) if str(referal).isdigit() else None
+        link = utils.get_subscription_link(rw_user.short_uuid) if rw_user else None
+        referal = (
+            int(referal) if str(referal).isdigit() and user_id != int(referal) else None
+        )
 
         model = NewUserDTO(id=user_id, referal=referal, link=link)
         return await self.user_repository.create_user(session, model)
@@ -114,6 +117,7 @@ class UserService:
         ticket = await self.ticket_repository.get_available_ticket_by_user_id(
             session, user.id
         )
+        db_user = await self.user_repository.get_user_by_id(session, user.id)
 
         if ticket:
             try:
@@ -121,7 +125,11 @@ class UserService:
                     chat_id=settings.admin_group_id,
                     message_thread_id=ticket.thread_id,
                     text=utils.format_support_subscription(
-                        subscription, user.full_name, user.id, user.username
+                        subscription=subscription,
+                        full_name=user.full_name,
+                        user_id=user.id,
+                        username=user.username,
+                        balance=db_user.balance,
                     ),
                 )
                 return
@@ -148,12 +156,17 @@ class UserService:
         ticket = await self.ticket_repository.update_ticket_thread_id(
             session, ticket, thread.message_thread_id
         )
+        db_user = await self.user_repository.get_user_by_id(session, ticket.creator_id)
 
         await bot.send_message(
             chat_id=settings.admin_group_id,
             message_thread_id=ticket.thread_id,
             text=utils.format_support_subscription(
-                subscription, user.full_name, user.id, user.username
+                subscription=subscription,
+                full_name=user.full_name,
+                user_id=user.id,
+                username=user.username,
+                balance=db_user,
             ),
         )
 
@@ -204,7 +217,10 @@ class UserService:
             settings.admin_group_id,
             message_thread_id=thread.message_thread_id,
             text=await self.format_admin_support_message(
-                ticket_number=ticket.id, user=msg.from_user, rw_user=rw_user
+                ticket_number=ticket.id,
+                user=msg.from_user,
+                rw_user=rw_user,
+                balance=user.balance,
             ),
         )
         await msg.copy_to(
@@ -269,3 +285,23 @@ class UserService:
         user = await self.user_repository.update_user_link(session, user_id, link)
 
         return user
+
+    async def fetch_user_by_thread(
+        self, session: AsyncSession, thread_id: int
+    ) -> Optional[User]:
+        ticket = await self.ticket_repository.get_ticket_by_thread_id(
+            session, thread_id=thread_id
+        )
+
+        return await self.user_repository.get_user_by_id(session, ticket.creator_id)
+
+    async def fetch_referal_by_thread(
+        self, session: AsyncSession, thread_id: int
+    ) -> Optional[User]:
+        ticket = await self.ticket_repository.get_ticket_by_thread_id(
+            session, thread_id=thread_id
+        )
+
+        return await self.user_repository.get_referal_by_user_id(
+            session, ticket.creator_id
+        )