Backfill only current posts: skip deleted, use latest update data

Previously backfill_follower sent all Create activities regardless
of whether they were later Deleted or Updated. Now it excludes
deleted sources and applies the latest Update's object_data so
new followers see the current version of each post.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

infrastructure/ap_inbox_handlers.py

@@ -101,7 +101,11 @@ async def backfill_follower(
     domain: str,
     origin_app: str | None = None,
 ) -> None:
-    """Deliver recent Create activities to a new follower's inbox."""
+    """Deliver recent *current* Create activities to a new follower's inbox.
+
+    Skips Creates whose source was later Deleted, and uses the latest
+    Update data when available (so the follower sees the current version).
+    """
     from shared.events.handlers.ap_delivery_handler import (
         _build_activity_json, _deliver_to_inbox,
     )
@@ -110,18 +114,68 @@ async def backfill_follower(
         APActivity.actor_profile_id == actor.id,
         APActivity.is_local == True,  # noqa: E712
         APActivity.activity_type == "Create",
+        APActivity.source_type.isnot(None),
+        APActivity.source_id.isnot(None),
     ]
     if origin_app is not None:
         filters.append(APActivity.origin_app == origin_app)
 
-    activities = (
+    creates = (
         await session.execute(
             select(APActivity).where(*filters)
             .order_by(APActivity.published.desc())
-            .limit(20)
+            .limit(40)
         )
     ).scalars().all()
 
+    if not creates:
+        return
+
+    # Collect source keys that have been Deleted
+    source_keys = {(c.source_type, c.source_id) for c in creates}
+    deleted_keys: set[tuple[str | None, int | None]] = set()
+    if source_keys:
+        deletes = (
+            await session.execute(
+                select(APActivity.source_type, APActivity.source_id).where(
+                    APActivity.actor_profile_id == actor.id,
+                    APActivity.activity_type == "Delete",
+                    APActivity.is_local == True,  # noqa: E712
+                )
+            )
+        ).all()
+        deleted_keys = {(d[0], d[1]) for d in deletes}
+
+    # For sources with Updates, grab the latest Update's object_data
+    updated_data: dict[tuple[str | None, int | None], dict] = {}
+    if source_keys:
+        updates = (
+            await session.execute(
+                select(APActivity).where(
+                    APActivity.actor_profile_id == actor.id,
+                    APActivity.activity_type == "Update",
+                    APActivity.is_local == True,  # noqa: E712
+                ).order_by(APActivity.published.desc())
+            )
+        ).scalars().all()
+        for u in updates:
+            key = (u.source_type, u.source_id)
+            if key not in updated_data and key in source_keys:
+                updated_data[key] = u.object_data or {}
+
+    # Filter to current, non-deleted Creates (limit 20)
+    activities = []
+    for c in creates:
+        key = (c.source_type, c.source_id)
+        if key in deleted_keys:
+            continue
+        # Apply latest Update data if available
+        if key in updated_data:
+            c.object_data = updated_data[key]
+        activities.append(c)
+        if len(activities) >= 20:
+            break
+
     if not activities:
         return