refactor: 消除所有 api-services-raw 残留调用，API 口径完全统一

- dashboardApi 新增 resolveTodo/ignoreTodo/batchResolveTodos/batchIgnoreTodos
- notificationsApi 新增 checkContracts/test
- settingsApi 新增 confirmRetirementPolicy
- socialInsuranceApi 新增 monthlyChanges/housingMonthlyChanges/housingActiveDeclaration
- Dashboard.tsx 替换 4 处 apiPatch
- Settings.tsx 替换 4 处 apiPost
- Notifications.tsx 替换 1 处 apiPost
- SocialInsurance.tsx 替换 4 处 apiGet
- AIAssistant.tsx 移除未使用的 apiPost 导入
- 所有页面零 api-services-raw 依赖

frontend/src/pages/Notifications.tsx

@@ -3,7 +3,6 @@ import { useQuery, useMutation, useQueryClient } from '@tanstack/react-query'
 import { toast } from 'sonner'
 import { Bell, CheckCircle, AlertCircle, Send, Settings as SettingsIcon, X } from 'lucide-react'
 import { notificationsApi } from '../lib/api-services'
-import { post as apiPost } from '../lib/api-services-raw'
 import Card from '../components/ui/Card'
 import Button from '../components/ui/Button'
 import EmptyState from '../components/ui/EmptyState'
@@ -52,7 +51,7 @@ export default function Notifications() {
   })
 
   const checkContractsMutation = useMutation({
-    mutationFn: () => apiPost('/notifications/check-contracts'),
+    mutationFn: () => notificationsApi.checkContracts(),
     onSuccess: () => {
       toast.success('合同到期检查已触发')
       queryClient.invalidateQueries({ queryKey: ['notification-logs'] })