Separate staff roles and protect message delivery with operator guides

src/core/services.py

@@ -80,10 +80,15 @@ class UserService:
     @staticmethod
     async def delete_user(session: AsyncSession, user_id: int) -> bool:
         """Удалить пользователя и все связанные данные"""
-        user = await session.get(User, user_id)
+        user = await session.scalar(select(User).where(User.id == user_id).with_for_update()
+                                    .execution_options(populate_existing=True))
         if not user:
             return False
         
+        from .config import ADMIN_IDS, CASHIER_IDS
+        if user.is_admin or user.is_cashier or user.telegram_id in set(ADMIN_IDS) | set(CASHIER_IDS):
+            return False
+
         # Keep records needed by draws, claims, chat history, or staff audit trails.
         # Cleanup may delete only users without linked data; moderation uses bans.
         from .database import Base
@@ -107,17 +112,6 @@ class UserService:
         await session.commit()
         return True
 
-    @staticmethod
-    async def set_admin(session: AsyncSession, telegram_id: int, is_admin: bool = True) -> bool:
-        """Установить/снять права администратора"""
-        result = await session.execute(
-            update(User)
-            .where(User.telegram_id == telegram_id)
-            .values(is_admin=is_admin)
-        )
-        await session.commit()
-        return result.rowcount > 0
-
     @staticmethod
     async def set_account_number(session, telegram_id, account_number):
         from sqlalchemy.exc import IntegrityError