refactor(sync): drop favorite-folder tracking and deal

tools/seed_preview_db.py

@@ -271,12 +271,12 @@ def _seed_task_records(
                 "backup_path": f"data/backup/app-{latest_day.strftime('%Y%m%d')}.db",
             },
         },
-        "folder_sync": {
-            "name": "folder_sync", "ok": True,
+        "ingest": {
+            "name": "ingest", "ok": True,
             "started_at": int(base + 20 * 3600),
-            "finished_at": int(base + 20 * 3600 + 8),
+            "finished_at": int(base + 20 * 3600 + 6),
             "error": None,
-            "summary": {"folders": 2, "added": 65, "removed": 0, "ok": True},
+            "summary": {"refs": 2, "added": 2, "ok": True},
         },
         "discovery": {
             "name": "discovery", "ok": True,