feat: 埋点统计系统 — 数据库存储 + 管理后台查询

后端：
- track_events 表存储埋点数据（事件类型、页面、数据、用户）
- track 路由改为写入数据库
- logs 路由新增 /track/stats 和 /track/list 查询接口

前端：
- 新增埋点统计页面（今日事件、7天趋势、热门事件）
- 支持按事件类型筛选
- 管理后台添加「埋点统计」入口

server/src/routes/logs.ts

@@ -1,6 +1,7 @@
 import { Router } from 'express'
 import fs from 'fs'
 import path from 'path'
+import pool from '../db/connection'
 import { requireAdmin } from '../middleware/requireAdmin'
 
 const router = Router()
@@ -143,4 +144,84 @@ router.get('/:date', requireAdmin, (req, res) => {
   }
 })
 
+/** 获取埋点统计 */
+router.get('/track/stats', requireAdmin, async (_req, res) => {
+  try {
+    // 今日统计
+    const [todayRows] = await pool.execute(
+      `SELECT event, COUNT(*) as count FROM track_events
+       WHERE DATE(created_at) = CURDATE()
+       GROUP BY event ORDER BY count DESC`
+    )
+
+    // 最近7天每日统计
+    const [dailyRows] = await pool.execute(
+      `SELECT DATE(created_at) as date, COUNT(*) as count FROM track_events
+       WHERE created_at >= DATE_SUB(CURDATE(), INTERVAL 7 DAY)
+       GROUP BY DATE(created_at) ORDER BY date DESC`
+    )
+
+    // 最近7天事件分布
+    const [eventRows] = await pool.execute(
+      `SELECT event, COUNT(*) as count FROM track_events
+       WHERE created_at >= DATE_SUB(CURDATE(), INTERVAL 7 DAY)
+       GROUP BY event ORDER BY count DESC LIMIT 10`
+    )
+
+    res.json({
+      code: 0,
+      data: {
+        today: todayRows,
+        daily: dailyRows,
+        events: eventRows
+      }
+    })
+  } catch (err) {
+    console.error('[Track] Stats error:', err)
+    res.status(500).json({ code: 50000, message: '获取埋点统计失败' })
+  }
+})
+
+/** 查询埋点事件 */
+router.get('/track/list', requireAdmin, async (req, res) => {
+  try {
+    const { event, page = '1', pageSize = '50' } = req.query
+    const pNum = Math.max(1, parseInt(page as string) || 1)
+    const pSize = Math.min(200, Math.max(1, parseInt(pageSize as string) || 50))
+    const offset = (pNum - 1) * pSize
+
+    let where = '1=1'
+    const params: any[] = []
+
+    if (event && typeof event === 'string') {
+      where += ' AND t.event = ?'
+      params.push(event)
+    }
+
+    const [countResult] = await pool.execute(
+      `SELECT COUNT(*) as total FROM track_events t WHERE ${where}`,
+      params
+    )
+    const total = (countResult as any[])[0].total
+
+    const [rows] = await pool.execute(
+      `SELECT t.*, u.nickname
+       FROM track_events t
+       LEFT JOIN users u ON t.user_id = u.id
+       WHERE ${where}
+       ORDER BY t.created_at DESC
+       LIMIT ? OFFSET ?`,
+      [...params, pSize, offset]
+    )
+
+    res.json({
+      code: 0,
+      data: { list: rows, total, page: pNum, pageSize: pSize }
+    })
+  } catch (err) {
+    console.error('[Track] List error:', err)
+    res.status(500).json({ code: 50000, message: '查询埋点失败' })
+  }
+})
+
 export default router