feat: 商业认证完整流程 + 通知时间过滤

商业认证:
- 申请页重写：商户名+说明字段，显示审核中/被拒/已通过状态
- 被拒绝显示原因，可重新申请
- 管理员拒绝时输入原因
- 商业核算页未认证用户点详情弹认证提示，跳转认证页面
- 删除项目仅管理员可见

通知:
- 只显示用户注册后的通知，避免角色变更后看到旧通知
- 搜索未收录通知只发管理员和高级编辑者

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

frontend/src/views/UserManagement.vue

@@ -27,8 +27,8 @@
       <div class="review-list">
         <div v-for="app in businessApps" :key="app._id || app.id" class="review-item">
           <div class="review-info">
-            <span class="review-name">{{ app.user_name || app.display_name }}</span>
-            <span class="review-reason">{{ app.reason }}</span>
+            <span class="review-name">{{ app.display_name || app.username }}</span>
+            <span class="review-reason">商户名：{{ app.business_name }}</span>
           </div>
           <div class="review-actions">
             <button class="btn-sm btn-approve" @click="approveBusiness(app)">通过</button>
@@ -101,7 +101,7 @@ import { ref, computed, onMounted } from 'vue'
 import { useAuthStore } from '../stores/auth'
 import { useUiStore } from '../stores/ui'
 import { api } from '../composables/useApi'
-import { showConfirm } from '../composables/useDialog'
+import { showConfirm, showPrompt } from '../composables/useDialog'
 
 const auth = useAuthStore()
 const ui = useUiStore()
@@ -248,8 +248,13 @@ async function approveBusiness(app) {
 
 async function rejectBusiness(app) {
   const id = app._id || app.id
+  const reason = await showPrompt('请输入拒绝原因（选填）：')
+  if (reason === null) return
   try {
-    const res = await api(`/api/business-applications/${id}/reject`, { method: 'POST' })
+    const res = await api(`/api/business-applications/${id}/reject`, {
+      method: 'POST',
+      body: JSON.stringify({ reason: reason || '' }),
+    })
     if (res.ok) {
       businessApps.value = businessApps.value.filter(item => (item._id || item.id) !== id)
       ui.showToast('已拒绝')