后端功能增强：全局异常处理、API控制器、JSP视图和单元测试

- 添加 GlobalExceptionHandler 全局异常处理
- 添加 ApiController REST API 控制器
- 更新 WebConfig 跨域配置和 ProductRepository 查询方法
- 新增 monitor/product-detail/profile JSP 视图页面
- 添加 FlashSaleServiceTest 秒杀服务单元测试
- 更新 application.yml 配置

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

@@ -0,0 +1,48 @@
+<template>
+  <div class="admin-flashsales">
+    <div class="page-header">
+      <h2 class="page-title">秒杀活动管理</h2>
+      <el-button type="primary">
+        <el-icon class="mr-1"><Plus /></el-icon>
+        创建秒杀
+      </el-button>
+    </div>
+    
+    <div class="content-card">
+      <el-table :data="[]" stripe>
+        <el-table-column prop="id" label="ID" width="80" />
+        <el-table-column prop="productName" label="商品名称" />
+        <el-table-column prop="flashPrice" label="秒杀价" />
+        <el-table-column prop="flashStock" label="秒杀库存" />
+        <el-table-column prop="startTime" label="开始时间" />
+        <el-table-column prop="endTime" label="结束时间" />
+        <el-table-column prop="status" label="状态" />
+        <el-table-column label="操作" width="200">
+          <template #default>
+            <el-button text type="primary" size="small">编辑</el-button>
+            <el-button text type="danger" size="small">删除</el-button>
+          </template>
+        </el-table-column>
+      </el-table>
+    </div>
+  </div>
+</template>
+
+<script setup lang="ts">
+</script>
+
+<style scoped lang="scss">
+.admin-flashsales {
+  .page-header {
+    @apply flex justify-between items-center mb-6;
+    
+    .page-title {
+      @apply text-2xl font-bold;
+    }
+  }
+  
+  .content-card {
+    @apply bg-white rounded-lg shadow-sm p-6;
+  }
+}
+</style>