refactor(i18n): U41 残余硬编码中文清零 — 工具函数+审计RDP标签+AIOps分析+Monitor残余+审批选项

18 文件 ~35 处 UI 硬编码中文→t()/i18n.t() 调用:
- agent-utils.ts timeAgo() 秒前/分钟前/小时前
- utils.ts formatDistanceToNow() 分钟前/小时前/天前
- request.ts 响应解析失败错误消息
- ActiveSessionsPanel/HistorySessionsPanel RDP 在线/历史会话标签
- MetricsExplorer 清除/已选/最近1小时
- HostMonitor 当前主机 subtitle
- AIAnalysisResult 证据链 (新增 useTranslation hook)
- capacity-predict.ts 容量预测摘要模板
- ApprovalResourcePage 阿里云/腾讯云/华为云
- ApprovalPermissionPage 堡垒机
- site-monitor/helpers.ts 频率/时间/证书天数格式化
- site-monitor/analytics.ts 证书剩余/检查失败/延迟波动事件
- middleware-monitor MwTargetChartsPanel/MwTrendChart/helpers.ts
- snmp-monitor SnmpMetricTrendChart/SnmpDeviceChartsPanel
- host-monitor/utils.ts 图表点数标签 + PortPolicyDialog 系统进程说明

新增 34 翻译键 (common.duration.secAgo/hourAgo/dayAgo + common.selected/
responseParseError/rdpActiveSessions/rdpHistorySessions/rdpSessionCount/
evidenceChain/last1Hour/currentHost + monitor.lbl 10键 + monitor.siteMonitor
8键 + approval.provider 3键 + approval.permType 1键 +
monitor.portPolicyDialog.systemProcessDesc + aiops.capacity.summary)

zh/en 7813→7847 对齐; tsc -b=0, npm build✓ (17.31s), ESLint=0/43/any=0,
go build=0, 17/17 测试通过

frontend/src/pages/monitor/site-monitor/observability/analytics.ts

@@ -130,7 +130,7 @@ export function analyzeSslResults(results: SiteResult[], task: SiteTask): SslObs
     if (r.status !== 'success') {
       pushEvent(events, r, i18n.t('monitor.lbl.siteRequestTimeout'), 'error', r.error_message);
     } else if (r.ssl_days_remaining != null && r.ssl_days_remaining < 30) {
-      pushEvent(events, r, `证书剩余 ${r.ssl_days_remaining} 天`, r.ssl_days_remaining <= 7 ? 'error' : 'warn', expiry);
+      pushEvent(events, r, i18n.t('monitor.siteMonitor.certRemaining', { days: r.ssl_days_remaining }), r.ssl_days_remaining <= 7 ? 'error' : 'warn', expiry);
     }
   }
   const chart = tooltipOrder(results)
@@ -158,10 +158,10 @@ function analyzeLatencyResults(results: SiteResult[], label: string): LatencyObs
     const latency = r.response_time ?? r.total_time ?? 0;
     const failed = r.status !== 'success';
     const spike = !failed && latency > spikeThreshold;
-    if (failed) pushEvent(events, r, `${label}失败`, 'error', r.error_message || r.remote_ip);
+    if (failed) pushEvent(events, r, i18n.t('monitor.siteMonitor.checkFailed', { label }), 'error', r.error_message || r.remote_ip);
     else if (spike) {
       spikeCount++;
-      pushEvent(events, r, `${label}延迟波动`, 'warn', fmtMs(latency));
+      pushEvent(events, r, i18n.t('monitor.siteMonitor.latencyFluctuation', { label }), 'warn', fmtMs(latency));
     }
     return { time: fmtTime(r.checked_at).slice(-5), latency, failed, spike };
   });