fix(frontend): 终端窗口壳问题修复

- 详情抽屉打开终端/RDP/文件浏览前先关闭抽屉，修复同 z-index 遮挡冲突
- 删除语义不通的黄灯按钮，绿灯随全屏状态切换 aria-label
- 连接指示点补充 role=status 与 sr-only 文案，不再仅靠颜色区分
- LiveMonitorDialog 接入 i18n；修复 TerminalDialog 乱码注释；全屏文案迁至 common 命名空间

frontend/src/components/server/ServerManager.tsx

@@ -128,7 +128,11 @@ export function ServerManager() {
   const getServerDisplayName = (server: JsonData) =>
     server.alias || server.cloud_instance_name || server.hostname || server.ip || "";
 
+  // 详情抽屉内打开终端/RDP/文件时先关闭抽屉，避免同 z-index 的 Sheet 遮挡弹窗 // Logan.Li
+  const closeDetailSheet = () => setDetailServer(null);
+
   const openTerminal = (server: JsonData) => {
+    closeDetailSheet();
     setTerminalServer({
       id: server.id,
       name: getServerDisplayName(server),
@@ -140,11 +144,13 @@ export function ServerManager() {
   };
 
   const openRdp = (server: JsonData) => {
+    closeDetailSheet();
     setRdpServer({ id: server.id, name: getServerDisplayName(server), ip: server.ip });
     setRdpOpen(true);
   };
 
   const openFileBrowser = (server: JsonData) => {
+    closeDetailSheet();
     setFileBrowserServer({ id: server.id, name: getServerDisplayName(server) });
     setFileBrowserOpen(true);
   };