fix(HEL-494): 网站市场客户端改为纯中枢 Facade，并迁移 iFinD 凭据到中枢

生产 gateway 不再读取 Tushare token 或实例化 TushareProvider/TushareClient；问财凭据经带鉴权的中枢接口加密入库，避免发版后 iFinD 未配置。

Co-authored-by: Cursor <cursoragent@cursor.com>
Co-authored-by: multica-agent <github@multica.ai>

backend/data/datahub/ifind_proxy.py

@@ -1,5 +1,6 @@
 from __future__ import annotations
 
+import logging
 import time
 from typing import Any
 
@@ -7,6 +8,8 @@ from backend.data.datahub.bridge import DatahubBridge
 from backend.data.datahub.errors import DatahubError
 from backend.data.providers.ifind_client import IfindError
 
+LOGGER = logging.getLogger("xiaobai.datahub")
+
 
 class HubIfindProxy:
     """Website-facing iFinD facade. Talks only to xiaobai-datahub."""
@@ -15,16 +18,20 @@ class HubIfindProxy:
         self._datahub = datahub
         self._status: dict[str, Any] | None = None
         self._status_at = 0.0
+        self._pending: tuple[str, str] | None = None
 
     @property
     def configured(self) -> bool:
         return bool(self.status().get("configured"))
 
     def set_credentials(self, refresh_token: str, access_token: str = "") -> None:
+        self._pending = (str(refresh_token or ""), str(access_token or ""))
         self._status = None
         self._status_at = 0.0
+        self._flush_credentials()
 
     def status(self) -> dict[str, Any]:
+        self._flush_credentials()
         now = time.monotonic()
         if self._status is not None and now - self._status_at < 30:
             return dict(self._status)
@@ -132,7 +139,18 @@ class HubIfindProxy:
             "sample_time": str(payload[0].get("time") or "") if payload else "",
         }
 
+    def _flush_credentials(self) -> None:
+        pending = self._pending
+        if pending is None or not self._datahub.settings.token:
+            return
+        try:
+            self._datahub.client.put_ifind_credentials(pending[0], pending[1])
+            self._pending = None
+        except DatahubError:
+            LOGGER.warning("datahub ifind credential push failed; will retry")
+
     def _rows(self, api_name: str, params: dict[str, Any]) -> list[dict[str, Any]]:
+        self._flush_credentials()
         try:
             response = self._datahub.client.query_api(api_name, params)
         except DatahubError as exc: