fix(network): auto-cache LAN iface for carrier when CLAWD_ETH_IFACE unset

First getWiredIfaceWithCarrier() result locks _lanMonitoredIface; subsequent
hasLanCableCarrier only reads that sysfs carrier so unplug reliably turns LAN off.
CLAWD_ETH_IFACE still overrides.

Made-with: Cursor

lib/network.js

@@ -62,9 +62,12 @@ function hasWiredCarrier() {
   return getWiredIfaceWithCarrier() !== null;
 }
 
+/** LAN 灯：未配 CLAWD_ETH_IFACE 时，首次见 carrier 的有线口会缓存，之后只读该口（拔线即灭） */
+let _lanMonitoredIface = null;
+
 /**
- * LAN 面板灯专用：若设置 CLAWD_ETH_IFACE，只认该口 carrier（拔网线必灭）；
- * 未设置时退回 hasWiredCarrier()（可能受其它网口影响，建议在 box 上配置 end0 等）。
+ * LAN 面板灯专用：优先 CLAWD_ETH_IFACE；否则自动锁定首次出现的 getWiredIfaceWithCarrier()，
+ * 之后仅看该口 carrier（避免「任意有线」与其它虚拟口混淆）。多口同时在线时仍以扫描序为准，可用手动 env 覆盖。
  */
 function hasLanCableCarrier() {
   const explicit = process.env.CLAWD_ETH_IFACE;
@@ -75,7 +78,20 @@ function hasLanCableCarrier() {
       return false;
     }
   }
-  return hasWiredCarrier();
+
+  if (_lanMonitoredIface) {
+    try {
+      return fs.readFileSync(`/sys/class/net/${_lanMonitoredIface}/carrier`, 'utf8').trim() === '1';
+    } catch (_) {
+      _lanMonitoredIface = null;
+      return false;
+    }
+  }
+
+  const wired = getWiredIfaceWithCarrier();
+  if (!wired) return false;
+  _lanMonitoredIface = wired;
+  return true;
 }
 
 function _tryPingInternet() {