feat: referal spec on registration

routes/auth.py

@@ -28,9 +28,21 @@ async def signup(req: UserRegistration, session: AsyncSession = Depends(get_db))
             raise HTTPException(status_code=409, detail="User already exists")
 
         password_hash = hash_password(req.password)
-        user = await users_repo.create(username=req.username, hashed_password=password_hash)
+        referal_id = None
+        if req.referal_code:
+            referal = await users_repo.get_user_by_ref_code(req.referal_code)
+            referal_id = referal.id if referal else None
+
+        user = await users_repo.create(
+            username=req.username, hashed_password=password_hash, referal_id=referal_id
+        )
         return JSONResponse(
-            UserInfo(username=user.username, telegram_id=user.telegram_id).model_dump(),
+            UserInfo(
+                username=user.username,
+                telegram_id=user.telegram_id,
+                subscription=None,
+                referal_code=user.referal_code,
+            ).model_dump(),
             status_code=201,
         )
     raise HTTPException(status_code=400, detail="Unsupported provider")