feat: 完成 P1 全部功能 + 修复 proxy 导出 + 切换 MySQL 端口至 14013

## P1 功能（20 项）
- 站内消息系统、家长仪表盘、学生考勤管理
- Excel 导入导出、用户批量导入、成绩导出
- 排课规则+自动排课+课表调整
- 成绩趋势+对比分析、密码安全策略、速率限制
- 数据变更日志、文件预览+存储策略、全文检索
- 依赖审计集成 CI、数据库定时备份、E2E 测试完善
- 通知偏好管理

## 基础设施修复
- src/proxy.ts: 将 middleware 导出重命名为 proxy（Next.js 16 要求）
- .env: MySQL 端口从 13002 切换至 14013
- scripts/create-db.ts: 新增数据库初始化脚本

## 架构文档同步
- 004_architecture_impact_map.md 和 005_architecture_data.json
  完整记录所有新增表、模块、路由、权限、依赖关系

.gitea/workflows/ci.yml

@@ -7,6 +7,8 @@ on:
   pull_request:
     branches:
       - main
+  schedule:
+    - cron: "0 2 * * *"  # 每天凌晨 2 点触发定时备份
 
 
 jobs:
@@ -128,3 +130,43 @@ jobs:
             nextjs-app
           
           echo "Deploy complete!"
+
+  security-audit:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-node@v4
+        with:
+          node-version: 20
+      - run: npm ci
+      - name: Run npm audit
+        run: npm audit --audit-level=moderate
+        continue-on-error: true
+      - name: Check for critical vulnerabilities
+        run: npm audit --audit-level=critical
+      - name: Upload audit report
+        if: always()
+        run: npm audit --json > audit-report.json
+      - uses: actions/upload-artifact@v3
+        if: always()
+        with:
+          name: security-audit-report
+          path: audit-report.json
+
+  scheduled-backup:
+    if: github.event_name == 'schedule'
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - name: Run database backup
+        env:
+          DATABASE_URL: ${{ secrets.DATABASE_URL }}
+          BACKUP_DIR: ./backups
+        run: |
+          chmod +x scripts/backup-db.sh
+          ./scripts/backup-db.sh
+      - uses: actions/upload-artifact@v3
+        with:
+          name: db-backup
+          path: backups/
+          retention-days: 30