接入运维真实 metrics：负载、请求错误率与服务探测

- 新增 GET /admin/ops/metrics 与进程内请求统计中间件
- 运维页展示 CPU/内存/磁盘、24h 曲线与 WS/DB/存储状态
- 去掉未使用的消息队列占位项

web/src/services/api.ts

@@ -90,6 +90,55 @@ export interface AdminStats {
   recent_logs?: OperationLog[]
 }
 
+/** 平台运维实时指标（当前 API 实例） */
+export interface OpsServiceStatus {
+  name: string
+  status: 'normal' | 'warning' | 'error' | string
+  detail?: string
+  latency_ms?: number
+  connections?: number
+}
+
+export interface OpsMetrics {
+  overall: 'normal' | 'warning' | 'error' | string
+  updated_at: string
+  instance: string
+  uptime_sec: number
+  services: OpsServiceStatus[]
+  load: {
+    cpu_percent: number
+    mem_percent: number
+    disk_percent: number
+    cpu_cores: number
+    mem_total_mb: number
+    mem_used_mb: number
+    disk_total_gb: number
+    disk_used_gb: number
+    go_goroutines: number
+    go_heap_mb: number
+  }
+  api: {
+    requests_last_24h: number[]
+    error_rate_last_24h: number[]
+    hours: number[]
+    qps: number
+    error_rate_now: number
+    window_requests: number
+    window_errors: number
+    total_requests: number
+    total_errors: number
+    total_5xx: number
+    in_flight: number
+  }
+  websocket: {
+    connections: number
+    agents: number
+    visitors: number
+  }
+}
+
+export const getOpsMetrics = () => get<OpsMetrics>('/admin/ops/metrics')
+
 export interface StatisticsKpis {
   total_sessions: number
   avg_response_time: number