fix: improve online detection when Clash API omits user metadata

Match connections by multiple auth keys, fall back to global traffic for
single-node setups, and document offline-status troubleshooting.

Co-authored-by: Cursor <cursoragent@cursor.com>

docs/troubleshooting.md

@@ -78,8 +78,23 @@ systemctl restart sing-box jiedian-panel
 
 ### 在线状态始终离线但客户端能连
 
-- 有流量时面板会按速率推断在线；若仍显示离线，执行 `curl -s -H "Authorization: Bearer $(grep CLASH_API_SECRET /opt/jiedian/.env | cut -d= -f2)" http://127.0.0.1:9090/connections | head` 查看连接 metadata 是否含 user 字段
-- 修改节点或升级后需重新渲染配置：`python3 /opt/jiedian/scripts/render-server.py && systemctl restart sing-box`
+面板通过 sing-box **Clash API** 判断在线。统计服务显示「正常」只代表 API 能访问，不代表能识别到连接。
+
+常见原因：
+
+1. **Clash API 未带 user 字段**（Hysteria2 旧配置未设置 `name`）→ 重新生成配置：
+   ```bash
+   python3 /opt/jiedian/scripts/render-server.py && systemctl restart sing-box
+   ```
+2. **仅有一个节点时**：新版面板会把所有活跃连接归到该节点；多节点需确保 hy2 用户 `name` 与 VLESS 的 UUID 一致。
+3. **客户端测速有延迟但面板仍离线**：在 VPS 上查看 Clash 连接列表：
+   ```bash
+   curl -s -H "Authorization: Bearer $(grep ^CLASH_API_SECRET= /opt/jiedian/.env | cut -d= -f2)" \
+     http://127.0.0.1:9090/connections | python3 -m json.tool | head -80
+   curl -s -H "Authorization: Bearer $(grep ^CLASH_API_SECRET= /opt/jiedian/.env | cut -d= -f2)" \
+     http://127.0.0.1:9090/traffic
+   ```
+   若 `connections` 为空但 `traffic` 有速率，说明在传流量但连接详情未上报，单节点场景面板会用全局速率推断在线。
 
 ### 面板打不开 / 404