feat(up): capture follower snapshots at ingest and backfill history

reaction_board/cli.py

@@ -39,6 +39,7 @@ from .services.favorites import FavoriteActionService
 from .services.folder_sync import FolderSyncService
 from .services.snapshot import SnapshotService
 from .services.telegram_poller import TelegramPoller
+from .services.up_profile import UpProfileService
 from .timeutil import next_daily_run, parse_hhmm, shanghai_date
 
 ROOT = Path(__file__).resolve().parent.parent
@@ -120,6 +121,12 @@ def _build_parser() -> argparse.ArgumentParser:
         "--preview", action="store_true",
         help="以预览模式启动（要求数据库含 preview:seeded=1 标记）",
     )
+    backfill = sub.add_parser(
+        "backfill-followers", parents=[common],
+        help="为历史视频回填 UP 粉丝数快照（只补空值）",
+    )
+    backfill.add_argument("--limit", type=int, default=None, help="最多处理多少个 UP")
+    backfill.add_argument("--dry-run", action="store_true", help="只统计待回填数量，不发请求")
     sub.add_parser("status", parents=[common], help="查看数据库状态（离线）")
     return parser
 
@@ -226,6 +233,33 @@ def cmd_sync(args, logger: JsonLogger) -> int:
         db.close()
 
 
+def cmd_backfill_followers(args, logger: JsonLogger) -> int:
+    store = ConfigStore(args.config, require_auth=False)
+    cfg = store.get()
+    db = _open_db(cfg, logger)
+    try:
+        repo = Repository(db)
+        client = _client(
+            cfg.bilibili.read, logger, pacer=Pacer(1.0, 1.6), retries=2
+        )
+        service = UpProfileService(repo, lambda: client, logger=logger)
+        started = int(time.time())
+        result = service.backfill(limit=args.limit, dry_run=args.dry_run)
+        payload = result.as_dict()
+        payload["dry_run"] = bool(args.dry_run)
+        payload["coverage"] = repo.up_follower_coverage()
+        payload["database"] = str(cfg.storage.database_path)
+        _record_task(
+            repo, "backfill_followers", ok=result.failed == 0,
+            started_at=started, finished_at=int(time.time()), payload=payload,
+            error="；".join(result.errors) if result.errors else None,
+        )
+        _print(payload)
+        return 0 if result.failed == 0 else 1
+    finally:
+        db.close()
+
+
 def cmd_snapshot(args, logger: JsonLogger) -> int:
     store = ConfigStore(args.config, require_auth=False)
     cfg = store.get()
@@ -673,6 +707,8 @@ def main(argv: Sequence[str] | None = None) -> int:
             return cmd_sync(args, logger)
         if args.command == "snapshot":
             return cmd_snapshot(args, logger)
+        if args.command == "backfill-followers":
+            return cmd_backfill_followers(args, logger)
         if args.command == "discover":
             return cmd_discover(args, logger)
         if args.command == "candidates":