refactor: 全量迁移前端 API 调用到统一 api-services 服务层

- 新建 api-services-raw.ts 导出原始 axios 方法供特殊端点使用
- 完成 api-services.ts 全领域覆盖（auth/employee/roster/dashboard/attendance/payroll/socialInsurance/commercialInsurance/termination/policies/evidence/audit/calendar/companyFiles/notifications/settings/ai/platform/portal/survey/search）
- 迁移所有 47+ 页面文件：pages/、pages/roster/、pages/portal/、pages/platform/、pages/auth/、pages/dashboard/、pages/compliance/
- 移除所有直接 import api from '../../lib/api' 引用
- 修复 Termination.tsx / WorkProcess.tsx 中 string|null 类型错误
- 修复 SocialInsurance.tsx 中 api-services-raw delete 导入名
- 修复 PlatformLogin.tsx 变量遮蔽问题
- tsc --noEmit 零错误，vite build 成功

frontend/src/pages/SalaryDashboard.tsx

@@ -9,7 +9,7 @@ import {
 import Card from '../components/ui/Card'
 import { Select } from '../components/ui/Input'
 import { InlineAlert } from '../components/ui/InlineAlert'
-import api from '../lib/api'
+import { salaryDashboardApi } from '../lib/api-services'
 
 /** 金额格式化 */
 const fmt = (n: number) => (n || 0).toLocaleString('zh-CN', { minimumFractionDigits: 2, maximumFractionDigits: 2 })
@@ -21,8 +21,7 @@ export default function SalaryDashboard() {
   const { data, isLoading } = useQuery<any>({
     queryKey: ['salary-dashboard', year],
     queryFn: async () => {
-      const res = await api.get('/salary/dashboard', { params: { year } }) as any
-      return res.data
+      return await salaryDashboardApi.data(Number(year))
     },
   })