fix: backfill account groups before priority reorder

backend/app/services/website_client.py

@@ -250,8 +250,8 @@ class Sub2ApiWebsiteClient:
                     return v
         return None
 
-    def _get_account_ids(self, endpoint: str = "/accounts") -> set[str] | None:
-        """拉取远端账号列表。成功返回 ID 集合（可能为空），解析失败返回 None。"""
+    def list_accounts(self, endpoint: str = "/accounts") -> list[dict[str, Any]] | None:
+        """拉取远端账号列表。成功返回账号 dict 列表，失败返回 None。"""
         try:
             resp = self._request("GET", endpoint)
         except Exception:
@@ -261,6 +261,13 @@ class Sub2ApiWebsiteClient:
         if items is None:
             logger.warning("account list unexpected format for %s", endpoint)
             return None
+        return [item for item in items if isinstance(item, dict)]
+
+    def _get_account_ids(self, endpoint: str = "/accounts") -> set[str] | None:
+        """拉取远端账号列表。成功返回 ID 集合（可能为空），解析失败返回 None。"""
+        items = self.list_accounts(endpoint)
+        if items is None:
+            return None
         ids: set[str] = set()
         for item in items:
             item_id = self.extract_id(item)