feat(HEL-490): 剩余行情改由数据中枢主线路提供

正式页面以 8766 为主线路，旧接口只作故障备用；compose 钉死全部 DATAHUB_READ_*，避免现网残留 0 造成假完成。

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

frontend/index.html

@@ -611,6 +611,7 @@
         <label class="form-field"><span>iFinD Refresh Token</span><input id="systemIfindTokenInput" type="password" autocomplete="off" maxlength="2048" placeholder="留空保留现有 Token"></label>
         <label class="switch-control"><input id="systemBackgroundRefresh" type="checkbox"><span>启用交易时段后台刷新</span></label>
         <p class="form-hint">所有用户读取同一份后台快照，页面不会随后台任务自动重绘。</p>
+        <div id="datahubRouteStatus" class="admin-refresh-status" data-tone="idle" role="status" aria-live="polite"><i data-lucide="database"></i><span>数据中枢线路待检查</span></div>
         <div id="adminRefreshStatus" class="admin-refresh-status" data-tone="idle" role="status" aria-live="polite"><i data-lucide="circle-dot"></i><span>尚未手动刷新</span></div>
         <div class="dialog-actions admin-inline-actions"><button id="adminRefreshButton" class="button" type="button"><i data-lucide="refresh-cw"></i>立即后台刷新</button><button class="button primary" type="submit">保存行情配置</button></div>
       </form>