fix: Change user_id type from UUID to str

src/backend/app/projects/project_schemas.py

@@ -278,7 +278,7 @@ async def one(db: Connection, project_id: uuid.UUID):
 
     async def all(
         db: Connection,
-        user_id: Optional[uuid.UUID] = None,
+        user_id: Optional[str] = None,
         skip: int = 0,
         limit: int = 100,
     ):