add admin check

src/services/users.py

@@ -0,0 +1,24 @@
+from fastapi import HTTPException
+
+from src.schemas.users import User
+from src.services.base import BaseService
+
+
+class UserService(BaseService):
+    async def get_user_by_username(self, username: str) -> User | None:
+        result = await self.session.user.get_one_or_none(username=username)
+        if result is None:
+            return None
+        return User.model_validate(result)
+
+    async def get_user_by_username_or_raise(self, username: str) -> User:
+        user = await self.get_user_by_username(username)
+        if user is None:
+            raise HTTPException(status_code=404, detail="User not found")
+        return user
+
+    async def validate_admin_user(self, username: str) -> User:
+        user = await self.get_user_by_username_or_raise(username)
+        if not user.is_superuser:
+            raise HTTPException(status_code=403, detail="Admin access required")
+        return user