feat: add last_technique_at to creators API endpoint

backend/routers/creators.py

@@ -46,11 +46,18 @@ async def list_creators(
         .correlate(Creator)
         .scalar_subquery()
     )
+    last_technique_sq = (
+        select(func.max(TechniquePage.created_at))
+        .where(TechniquePage.creator_id == Creator.id)
+        .correlate(Creator)
+        .scalar_subquery()
+    )
 
     stmt = select(
         Creator,
         technique_count_sq.label("technique_count"),
         video_count_sq.label("video_count"),
+        last_technique_sq.label("last_technique_at"),
     ).where(Creator.hidden != True)  # noqa: E712
 
     # Genre filter

backend/schemas.py

@@ -358,6 +358,7 @@ class CreatorBrowseItem(CreatorRead):
     """Creator with technique and video counts for browse pages."""
     technique_count: int = 0
     video_count: int = 0
+    last_technique_at: datetime | None = None
 
 
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