fix: close data integrity and hot-reload review findings

Backfill same-day snapshots for newly added or restored videos, preserve successful fan snapshots on resume, persist incomplete state before forced re-runs, and split collection completion from backup completion so failed backups can retry without API calls. Reject missing data payloads instead of treating them as empty folders, guard against mass-unfav on suspicious empty remote folders, rebuild Bilibili clients when credentials change, recompute primary folder ownership from active relations with per-folder fav_time, preserve original titles for dropped invalid videos, poll config every 60 seconds, and fix favsort verify interval and mixed resource types.

reaction_board/bilibili/client.py

@@ -262,6 +262,20 @@ class BilibiliClient:
             raise self._api_error(payload)
         return payload
 
+    @staticmethod
+    def _data_list(payload: Mapping[str, Any], name: str) -> list[Any]:
+        """区分“真实空数组”与“协议缺字段”。
+
+        实测空收藏夹返回 ``{"code":0,"data":[]}``；缺少 ``data`` 或为 ``null``
+        都不是已知契约，必须中止，避免被误判成空收藏夹后批量改状态。
+        """
+        if "data" not in payload:
+            raise BilibiliProtocolError(f"{name} 响应缺少 data 字段")
+        data = payload["data"]
+        if not isinstance(data, list):
+            raise BilibiliProtocolError(f"{name} data 不是数组")
+        return data
+
     # ------------------------------------------------------------ fav
 
     def fav_ids(self, media_id: int) -> list[FavId]:
@@ -269,11 +283,7 @@ class BilibiliClient:
             f"{BASE}/x/v3/fav/resource/ids?media_id={int(media_id)}&platform=web"
         )
         payload = self.get_json(url)
-        data = payload.get("data")
-        if data is None:
-            data = []
-        if not isinstance(data, list):
-            raise BilibiliProtocolError("fav/resource/ids data 不是数组")
+        data = self._data_list(payload, "fav/resource/ids")
         out: list[FavId] = []
         for index, item in enumerate(data):
             if not isinstance(item, Mapping):
@@ -320,11 +330,7 @@ class BilibiliClient:
                 f"&platform=web&folder_mid={fmid}&folder_id={int(media_id)}"
             )
             payload = self.get_json(url)
-            data = payload.get("data")
-            if data is None:
-                data = []
-            if not isinstance(data, list):
-                raise BilibiliProtocolError("fav/resource/infos data 不是数组")
+            data = self._data_list(payload, "fav/resource/infos")
             chunk_set = set(chunk)
             for item in data:
                 if not isinstance(item, Mapping):

reaction_board/bilibili/provider.py

@@ -0,0 +1,38 @@
+# -*- coding: utf-8 -*-
+"""按账号角色提供 B 站客户端，并在凭据变化时自动重建。"""
+
+from __future__ import annotations
+
+from typing import Any, Callable
+
+from ..config import ConfigStore
+from .client import BilibiliClient
+
+
+class ClientProvider:
+    """缓存客户端；仅当 ``mid`` / ``cookie`` / ``csrf`` 变化时重建。
+
+    ``factory`` 负责固化该角色的限速与重试策略，因此重建不会丢失这些设置。
+    """
+
+    def __init__(
+        self,
+        store: ConfigStore,
+        role: str,
+        factory: Callable[[Any], BilibiliClient],
+    ) -> None:
+        if role not in {"read", "write"}:
+            raise ValueError(f"未知账号角色: {role}")
+        self.store = store
+        self.role = role
+        self.factory = factory
+        self._key: tuple[int, str, str] | None = None
+        self._client: BilibiliClient | None = None
+
+    def get(self) -> BilibiliClient:
+        credentials = getattr(self.store.get().bilibili, self.role)
+        key = (credentials.mid, credentials.cookie, credentials.csrf)
+        if self._client is None or key != self._key:
+            self._client = self.factory(credentials)
+            self._key = key
+        return self._client