feat: datetimes with timezones

repositories/board.py

@@ -1,4 +1,4 @@
-from datetime import datetime
+from datetime import datetime, timezone
 from typing import Optional
 
 from sqlalchemy import select
@@ -30,7 +30,7 @@ class BoardRepository(BaseRepository):
 
     async def create(self, data: CreateBoardSchema) -> Board:
         board_data = data.model_dump()
-        board_data["created_at"] = datetime.now()
+        board_data["created_at"] = datetime.now(timezone.utc)
         board = Board(**board_data)
         self.session.add(board)
         await self.session.commit()