refactor(frontend): P1-P2 架构统一 — utils/hooks/api 模块化

P1:
- utils/storage.ts、theme.ts、validate.ts + index 统一出口
- request/store/useTheme 接入 storage；清零 confirm/alert
- PipelineManager、TerminalAuditTab 拆分子模块（<700行红线）

P2:
- api/monitor、api/deploy 子目录化
- hooks/api 扩展：servers/pipelines/alerts/audit/sessionCommands
- PipelineManager、AuditOperationsTab 接入 TanStack Query

frontend/src/utils/request.ts

@@ -1,4 +1,5 @@
 import { useUserStore } from '@/store';
+import { getToken, clearToken } from './storage';
 
 const API_PREFIX = '/api/v1';
 
@@ -52,7 +53,7 @@ export function getWsBase(): string {
 }
 
 export function getAuthToken(): string {
-  return useUserStore.getState().token || localStorage.getItem('token') || '';
+  return getToken();
 }
 
 // eslint-disable-next-line @typescript-eslint/no-explicit-any
@@ -89,6 +90,7 @@ async function request<T = any>(
   });
 
   if (response.status === 401) {
+    clearToken();
     useUserStore.getState().logout();
     window.location.href = '/login';
     throw new Error('登录已过期，请重新登录');