quick fix

src/daemon_boyfriend/services/opinion_service.py

@@ -1,7 +1,7 @@
 """Opinion Service - manages bot opinion formation on topics."""
 
 import logging
-from datetime import datetime
+from datetime import datetime, timezone
 
 from sqlalchemy import select
 from sqlalchemy.ext.asyncio import AsyncSession
@@ -77,7 +77,7 @@ class OpinionService:
         )
         opinion.interest_level = max(0.0, min(1.0, opinion.interest_level))
 
-        opinion.last_reinforced_at = datetime.utcnow()
+        opinion.last_reinforced_at = datetime.now(timezone.utc)
 
         logger.debug(
             f"Updated opinion on '{topic}': sentiment={opinion.sentiment:.2f}, "