feat: 删除JSP视图层，完善评价和通知系统，新增拼团模块

- 删除所有 JSP 页面（20个文件），前端完全迁移至 Vue 3 SPA
- 完善评价系统：ReviewDialog 组件、用户评价历史页、评价状态检查API
- 新增通知系统：Notification 实体/仓库/服务/控制器，NotificationCenter 接入真实API
- 新增拼团模块：GroupBuying 全套后端和前端页面
- 修复 review check API 参数双重包装导致请求格式错误
- 修复通知 API 路径缺少 /api 前缀和响应格式处理
- MessageListenerService 集成 NotificationService 创建持久化通知

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

flash-sale-frontend/src/pages/admin/favorites.vue

@@ -93,14 +93,10 @@ onMounted(() => { reloadData() })
 .page-subtitle { @apply text-sm text-slate-500 mt-1; }
 .actions { display:flex; gap:12px; }
 .stats-grid { display:grid; grid-template-columns:repeat(4,minmax(0,1fr)); gap:16px; }
-.mini-stat { @apply rounded-xl text-white p-5 shadow-sm; }
-.mini-stat.blue { background:linear-gradient(135deg,#3b82f6,#2563eb); }
-.mini-stat.green { background:linear-gradient(135deg,#10b981,#059669); }
-.mini-stat.orange { background:linear-gradient(135deg,#f59e0b,#ea580c); }
-.mini-stat.purple { background:linear-gradient(135deg,#8b5cf6,#7c3aed); }
+.mini-stat { @apply rounded-xl p-5 shadow-sm; background:#fffaf2; color:#171715; border:1px solid #d8cebf; box-shadow:0 10px 24px rgba(23,22,20,0.04); }
 .mini-stat__value { @apply text-3xl font-bold; }
 .mini-stat__label { @apply text-sm opacity-90 mt-2; }
-.panel-card { @apply bg-white rounded-xl shadow-sm p-5; }
+.panel-card { @apply bg-white rounded-xl p-5; border:1px solid #d8cebf; box-shadow:0 10px 24px rgba(23,22,20,0.04); }
 .filter-card { display:grid; grid-template-columns:1fr 100px; gap:12px; }
 .table-footer { @apply flex justify-end mt-4; }
 </style>