refactor(q1): src/api 全量清零 any + types/monitor 扩展输入 DTO

ROADMAP Q1 推进（前端类型安全治理 in_progress）:

- src/api/ 整个目录 any 清零（含 monitor/ deploy/ 子目录 12+ 文件）
  create/update 入参 any -> Record<string, unknown> / object
  mock 桩 trace/grafana 对接 types/ 标准类型（Trace/GrafanaDashboard）
  典型接口 LdapFormData/ProbeForm 等强类型表单用 object 接收
- types/monitor.ts 扩展 ~150 行接口:
  ZabbixDatasource / AlertSilence / 7 个输入 DTO
  Trace / TraceSpan / TraceServiceMetrics / GrafanaDashboard / DashboardPanel
  HealthProbeInput

验证:
- 整个 src/api/ 目录 any=0
- ESLint no-explicit-any: 995 -> 937 (本项目此轮贡献 -58)
- tsc -b 零错误, npm run build ✓ (17.06s)
- API 回归 8/8 核心端点通过, Docker 部署 healthy

backend/static/assets/credential-Cg1BP64k.js

@@ -0,0 +1 @@
+import{h as t}from"./index-o4rKtKfJ.js";const a={list:e=>t.get("/credentials",e),get:e=>t.get(`/credentials/${e}`),create:e=>t.post("/credentials",e),update:(e,s)=>t.put(`/credentials/${e}`,s),delete:e=>t.delete(`/credentials/${e}`),toggleActive:(e,s)=>t.put(`/credentials/${e}`,{is_active:s})},r={assign:(e,s)=>t.post(`/servers/${e}/assign-credential`,{credential_id:s})};export{a as c,r as s};