refactor(frontend): P0 API 层收口与 http 统一

- 统一 http.ts baseURL：get/post/download/upload 均走 resolveApiUrl
- agentUtils 下沉至 lib/agent-utils，API 层移除对 components 的依赖
- 扩展 metricsApi/snmpApi/prometheusProxyApi/zabbixProxyApi
- 扩展 pipelineApi/credentialApi 覆盖流水线与凭证场景
- 14 个组件/页面禁止直连 http，统一走 @/services/api

frontend/src/components/deploy/WorkspaceTermDialog.tsx

@@ -11,7 +11,7 @@ import 'xterm/css/xterm.css';
 import { Maximize2, Minimize2, X, FolderOpen } from 'lucide-react';
 import { cn } from '@/lib/utils';
 import { useUserStore } from '@/store';
-import http from '@/services/http';
+import { pipelineApi } from '@/services/api';
 
 interface WorkspaceTermDialogProps {
   open: boolean;
@@ -40,7 +40,7 @@ export function WorkspaceTermDialog({
   // 获取 workspace 路径
   useEffect(() => {
     if (!open || !runId) return;
-    http.get(`/pipelines/runs/${runId}/workspace`)
+    pipelineApi.getWorkspace(runId)
       .then(( data: any) => setWorkspace(data?.workspace_path || ''))
       .catch(() => {});
   }, [open, runId]);