feat(link): ConnectionHub 统一 WiFi/ECAT/BLE 端点与健康态

各页不再各自读写 dcu_esp_ip / dcu_ecat_adapter：deviceLink 提供
wifiBaseUrl/ecatPost/adapter API，OTA/CAN/motor/ecat_load/lab 走同一入口。
连接灯只覆盖在线布尔，保留调用方语义文案。

js/app.js

@@ -34,6 +34,7 @@ import {
   updateStagesFromRelayState, updateSystemStatusUi
 } from './ota/stages.js';
 import { startEcatLoadPoller } from './ota/ecat_load.js';
+import { deviceLink } from './common/device-link.js';
 import {
   handleFileSelect, pickFileViaFSAPI, setupDropZone,
   parseIntelHex, isIntelHexText, convertHexFileToBin,
@@ -50,14 +51,15 @@ function formatPercent(value) {
   if (!Number.isFinite(value)) return '--';
   return value.toFixed(1).replace(/\.0$/, '') + '%';
 }
+/** 设备 IP：优先本页 #espIp 输入框，否则 ConnectionHub。
+ *  只在值变化时 setIp——Owner 会把 set-ip 当成立即重探，读路径每次写会 1Hz 风暴。 */
 function getEspIp() {
   var el = document.getElementById('espIp');
   var ip = el && el.value ? el.value.trim() : '';
-  if (!ip) {
-    try { ip = (localStorage.getItem('dcu_esp_ip') || '').trim(); } catch (_) {}
+  if (!ip) return deviceLink.getIp();
+  if (ip !== deviceLink.getIp()) {
+    try { deviceLink.setIp(ip); } catch (_) {}
   }
-  if (!ip) ip = '192.168.31.127';
-  try { localStorage.setItem('dcu_esp_ip', ip); } catch (_) {}
   return ip;
 }
 function getBaseUrl() {
@@ -277,11 +279,11 @@ startEcatLoadPoller();
 var ipInput = document.getElementById('espIp');
 if (ipInput) {
   try {
-    var savedIp = localStorage.getItem('dcu_esp_ip');
+    var savedIp = deviceLink.getIp();
     if (savedIp && savedIp.trim()) ipInput.value = savedIp.trim();
   } catch (_) {}
   ipInput.addEventListener('change', function () {
-    try { localStorage.setItem('dcu_esp_ip', ipInput.value.trim() || '192.168.31.127'); } catch (_) {}
+    try { deviceLink.setIp(ipInput.value.trim() || '192.168.31.127'); } catch (_) {}
     window.consecutivePollFailures = 0;
     addLog('I', '系统', 'IP 已修改，重新启动轮询...');
     if (!window.statusPollInFlight) {