fix: preserve live Nginx entry when saved draft differs

frontend/src/locales/en-US.json

@@ -902,6 +902,7 @@
     "saveDomain": "Save domain",
     "restartRequired": "Gateway mode saved; switching between Go and Nginx requires restarting the management service",
     "siteActivationRequired": "Entry saved; prepare and enable the Nginx site below for first use",
+    "pendingEntry": "Nginx still serves {address}; save to validate and apply the new entry",
     "applied": "Public entry updated; Nginx configuration is active",
     "saveFailed": "Could not save domain",
     "dns": "DNS",

frontend/src/locales/zh-CN.json

@@ -902,6 +902,7 @@
     "saveDomain": "保存域名",
     "restartRequired": "入口模式已保存；切换 Go 与 Nginx 模式需重启管理服务",
     "siteActivationRequired": "入口已保存；首次启用站点请到下方准备并启用 Nginx",
+    "pendingEntry": "当前 Nginx 仍使用 {address}；点击保存将校验并更新入口",
     "applied": "公网入口已更新，Nginx 配置已生效",
     "saveFailed": "保存域名失败",
     "dns": "DNS 解析",

frontend/src/views/settings/components/GatewaySettings.vue

@@ -55,6 +55,7 @@
 
       <el-alert v-if="tlsStatus?.restart_required" type="warning" :closable="false" :title="$t('tls.restartRequired')" style="margin-top:12px" />
       <el-alert v-else-if="entry.mode === 'nginx' && nginxSetup?.site_stage === 'none' && tlsStatus?.configured_domain" type="info" :closable="false" :title="$t('tls.siteActivationRequired')" style="margin-top:12px" />
+      <el-alert v-else-if="entry.mode === 'nginx' && tlsStatus?.public_base && tlsStatus?.configured_public_base !== tlsStatus?.public_base" type="warning" :closable="false" :title="$t('tls.pendingEntry', { address: tlsStatus.public_base })" style="margin-top:12px" />
       <el-alert v-if="tlsStatus?.management_direct_public" type="warning" :closable="false" :title="$t('tls.directPortWarning')" style="margin-top:12px" />
     </el-card>