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>

xiaobai-datahub/datahub/httpapp.py

@@ -76,6 +76,11 @@ class HubRequestHandler(BaseHTTPRequestHandler):
             payload = self.hub.api.query_api(body)
             self._json(payload, HTTPStatus.OK)
             return
+        if path == "/v1/credentials/ifind" and method == "POST":
+            body = self._read_json()
+            payload = self.hub.put_ifind_credentials(body)
+            self._json(payload, HTTPStatus.OK)
+            return
         payload = self.hub.api.handle(path, parse_query(query))
         self._json(payload, HTTPStatus.OK)