feat(fai): make content hash updated at timezone-naive (#5813)

Author: sahil485

servers/fai/src/fai/models/db/content_hash_db.py

@@ -1,4 +1,4 @@
-from datetime import UTC, datetime
+from datetime import datetime
 
 from sqlalchemy import Column, DateTime, Index, String
 
@@ -19,8 +19,8 @@ class ContentHashDb(Base):
     content_hash = Column(String, nullable=False, comment="SHA-256 hash of page markdown or endpoint document content")
 
     # Metadata
-    indexed_at = Column(DateTime, nullable=False, default=lambda: datetime.now(UTC))
-    updated_at = Column(DateTime, nullable=False, default=lambda: datetime.now(UTC), onupdate=lambda: datetime.now(UTC))
+    indexed_at = Column(DateTime, nullable=False, default=datetime.utcnow)
+    updated_at = Column(DateTime, nullable=False, default=datetime.utcnow, onupdate=datetime.utcnow)
 
     __table_args__ = (
         Index("idx_content_hashes_domain", "domain"),

servers/fai/src/fai/routes/content_hash.py

@@ -5,7 +5,7 @@
 The actual diffing logic lives in the fai-reindexing service.
 """
 
-from datetime import UTC, datetime
+from datetime import datetime
 
 from fastapi import Body, Depends
 from fastapi.encoders import jsonable_encoder
@@ -99,7 +99,7 @@ async def batch_upsert_content_hashes(
 
             if existing:
                 existing.content_hash = entry.content_hash
-                existing.updated_at = datetime.now(UTC)
+                existing.updated_at = datetime.utcnow()
             else:
                 new_hash = ContentHashDb(domain=domain, parent_id=entry.parent_id, content_hash=entry.content_hash)
                 db.add(new_hash)