refactor(frontend): API 子模块化、大组件拆分与 TanStack Query hooks

P1: kubernetes/system API 拆为子目录模块，导出工具下沉到 lib/export-utils，
    http 统一 buildApiUrl/getWsBase；HostMonitor、DeploymentEdit* 拆至子组件。

P2: 新增 hooks/api（queryKeys、useTerminalSessions、useHostMonitor），
    TerminalSessionsTab 与 HostMonitor 接入 TanStack Query。

P3: 保留 services/api 路径，未迁移至 api/ 目录。

backend/static/assets/sparkles-rPZivnlW.js

@@ -0,0 +1 @@
+import{i as a}from"./index-Dmami9WE.js";const e=[["path",{d:"M11.017 2.814a1 1 0 0 1 1.966 0l1.051 5.558a2 2 0 0 0 1.594 1.594l5.558 1.051a1 1 0 0 1 0 1.966l-5.558 1.051a2 2 0 0 0-1.594 1.594l-1.051 5.558a1 1 0 0 1-1.966 0l-1.051-5.558a2 2 0 0 0-1.594-1.594l-5.558-1.051a1 1 0 0 1 0-1.966l5.558-1.051a2 2 0 0 0 1.594-1.594z",key:"1s2grr"}],["path",{d:"M20 2v4",key:"1rf3ol"}],["path",{d:"M22 4h-4",key:"gwowj6"}],["circle",{cx:"4",cy:"20",r:"2",key:"6kqj1y"}]],r=a("sparkles",e);export{r as S};