feat(i18n): 安全审计模块全量国际化 — 7 文件硬编码中文改翻译键 + audit 命名空间(89 键)

迁移文件:
- AuditOperationsTab.tsx — 操作审计(搜索/筛选/虚拟滚动表格/详情弹窗/统计弹窗)
- TerminalAuditTab.tsx — 终端审计子标签(在线/历史/命令)
- LoginLogsTab.tsx — 登录日志(DataTable + 状态筛选 + 登录方式)
- ActiveSessionsPanel.tsx — 在线会话(自动刷新 + 阻断确认 + 实时监控)
- HistorySessionsPanel.tsx — 历史会话(回放/下载录制)
- SessionCommandsPanel.tsx — 会话命令(虚拟滚动)
- helpers.tsx — formatDuration/getStatusBadge (i18n.t 非组件模式)

翻译键: audit 命名空间 89 键 (operations/login/terminal 三子域)
  + common.duration 时长单位(秒/分/时)
总键数: 481→610, 命名空间: 8→9 (common/menu/header/login/dashboard/server/alert/approval/audit)
zh-CN/en-US 完全对齐, tsc -b=0, npm build✓, 17/17 测试通过

frontend/src/locales/en-US.json

@@ -71,7 +71,14 @@
     "operationSuccess": "Operation succeeded",
     "operationFailed": "Operation failed",
     "loadFailed": "Failed to load",
-    "saveFailed": "Failed to save"
+    "saveFailed": "Failed to save",
+    "duration": {
+      "sec": "{{count}}s",
+      "min": "{{count}}m",
+      "minSec": "{{m}}m {{s}}s",
+      "hour": "{{count}}h",
+      "hourMin": "{{h}}h {{m}}m"
+    }
   },
   "menu": {
     "dashboard": "Dashboard",
@@ -545,5 +552,107 @@
       "templateNotLoaded": "Template not loaded",
       "pleaseFill": "Please fill in \"{{label}}\""
     }
+  },
+  "audit": {
+    "operations": {
+      "searchPlaceholder": "Search audit logs...",
+      "allModules": "All Modules",
+      "allActions": "All Actions",
+      "noData": "No audit logs",
+      "viewDetail": "View Details",
+      "totalLogs": "{{count}} logs",
+      "virtualScroll": "virtual scroll",
+      "detailTitle": "Audit Log Details",
+      "statsTitle": "Audit Statistics",
+      "noStats": "No statistics available",
+      "topModules": "Top Modules",
+      "topUsers": "Active Users",
+      "col": {
+        "time": "Time",
+        "user": "User",
+        "module": "Module",
+        "actionType": "Action",
+        "resource": "Resource",
+        "ip": "IP",
+        "result": "Result",
+        "detail": "Detail"
+      },
+      "detailCol": {
+        "userId": "User ID",
+        "ipAddress": "IP Address",
+        "userAgent": "User-Agent",
+        "message": "Message"
+      },
+      "stats": {
+        "totalLogs": "Total Logs",
+        "todayLogs": "Today",
+        "successCount": "Success",
+        "failureCount": "Failed"
+      }
+    },
+    "login": {
+      "searchPlaceholder": "Search user/IP/location...",
+      "noData": "No login logs",
+      "all": "All",
+      "col": {
+        "loginTime": "Login Time",
+        "user": "User",
+        "loginType": "Method",
+        "ip": "IP",
+        "location": "Location",
+        "browser": "Browser/OS",
+        "status": "Status"
+      },
+      "type": {
+        "password": "Password",
+        "ldap": "LDAP",
+        "token": "Token",
+        "oauth": "OAuth"
+      }
+    },
+    "terminal": {
+      "searchUserServer": "Search user/server...",
+      "searchUserServerIp": "Search user/server/IP...",
+      "searchUserCommand": "Search user/command...",
+      "sessionIdPlaceholder": "Session ID (optional)",
+      "noActive": "No active sessions",
+      "noHistory": "No history sessions",
+      "noCommands": "No command records",
+      "totalCommands": "{{count}} commands",
+      "virtualScroll": "virtual scroll",
+      "autoRefresh": "Auto Refresh",
+      "autoRefreshHintOn": "Auto-refresh every {{sec}}s · click to disable",
+      "autoRefreshHintOff": "Click to enable auto-refresh",
+      "killTitle": "Terminate Session",
+      "killConfirm": "Force disconnect user \"{{user}}\"'s current session?",
+      "killConfirmBtn": "Terminate",
+      "liveMonitor": "Live Monitor",
+      "replay": "Replay",
+      "downloadRecord": "Download Recording",
+      "tab": {
+        "active": "Active Sessions",
+        "history": "History Sessions",
+        "commands": "Session Commands"
+      },
+      "col": {
+        "id": "ID",
+        "user": "User",
+        "targetServer": "Target Server",
+        "port": "Port",
+        "startTime": "Start Time",
+        "endTime": "End Time",
+        "duration": "Duration",
+        "status": "Status",
+        "actions": "Actions",
+        "command": "Command",
+        "outputSize": "Output Size",
+        "sessionRef": "Session"
+      },
+      "status": {
+        "active": "Active",
+        "failed": "Failed",
+        "closed": "Closed"
+      }
+    }
   }
 }