fix(widget): make connection errors actionable

replypier-test/README.md

@@ -60,9 +60,9 @@ npm start
 
 ## Troubleshooting
 
-- **"Chat can't load on 'localhost'"** — the origin isn't in your organization's allowed
-  domains (Organization settings). The port matters: `localhost:3000` allowed does not
-  permit `localhost:3010`.
+- **“客服暂时无法连接”** — check the browser console and the widget-data request in
+  Network for network, HTTP, or CORS failures. If the request was rejected by CORS,
+  check the page origin against the organization's allowed domain, including its port.
 - **Dashboard placement settings not applying** — almost always a stale loader. Check the
   served file has the newer features: `curl -s <loader-url> | grep -c sidebar-left`.
 - **Buttons do nothing on the gallery pages** — the loader failed to load; the page shows