fix part 3

backend/app/database/models/board_image.py

@@ -1,10 +1,10 @@
 """BoardImage database model - junction table for boards and images."""
 
-from datetime import datetime, timezone
+from datetime import datetime
 from typing import TYPE_CHECKING
 from uuid import UUID, uuid4
 
-from sqlalchemy import DateTime, ForeignKey, Integer
+from sqlalchemy import DateTime, ForeignKey, Integer, func
 from sqlalchemy.dialects.postgresql import JSONB
 from sqlalchemy.dialects.postgresql import UUID as PGUUID
 from sqlalchemy.orm import Mapped, mapped_column, relationship
@@ -52,9 +52,9 @@ class BoardImage(Base):
         PGUUID(as_uuid=True), ForeignKey("groups.id", ondelete="SET NULL"), nullable=True
     )
 
-    created_at: Mapped[datetime] = mapped_column(DateTime, nullable=False, default=lambda: datetime.now(timezone.utc))
+    created_at: Mapped[datetime] = mapped_column(DateTime, nullable=False, server_default=func.now())
     updated_at: Mapped[datetime] = mapped_column(
-        DateTime, nullable=False, default=lambda: datetime.now(timezone.utc), onupdate=lambda: datetime.now(timezone.utc)
+        DateTime, nullable=False, server_default=func.now(), onupdate=func.now()
     )
 
     # Relationships