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

src/modules/announcements/components/admin-announcements-view.tsx

@@ -0,0 +1,65 @@
+"use client"
+
+import { useState } from "react"
+import { useRouter } from "next/navigation"
+import { PlusCircle } from "lucide-react"
+
+import { Button } from "@/shared/components/ui/button"
+import { Dialog, DialogContent, DialogHeader, DialogTitle } from "@/shared/components/ui/dialog"
+
+import { AnnouncementForm } from "./announcement-form"
+import { AnnouncementList } from "./announcement-list"
+import type { Announcement, AnnouncementStatus } from "../types"
+
+export function AdminAnnouncementsView({
+  announcements,
+  grades = [],
+  classes = [],
+  initialStatus,
+}: {
+  announcements: Announcement[]
+  grades?: { id: string; name: string }[]
+  classes?: { id: string; name: string }[]
+  initialStatus?: AnnouncementStatus
+}) {
+  const router = useRouter()
+  const [createOpen, setCreateOpen] = useState(false)
+
+  const handleOpenChange = (open: boolean) => {
+    setCreateOpen(open)
+    if (!open) router.refresh()
+  }
+
+  return (
+    <div className="flex h-full flex-col space-y-8 p-8">
+      <div className="flex items-center justify-between space-y-2">
+        <div>
+          <h2 className="text-2xl font-bold tracking-tight">Announcements</h2>
+          <p className="text-muted-foreground">
+            Create and manage school-wide announcements.
+          </p>
+        </div>
+        <Button onClick={() => setCreateOpen(true)}>
+          <PlusCircle className="mr-2 h-4 w-4" />
+          New Announcement
+        </Button>
+      </div>
+
+      <AnnouncementList
+        announcements={announcements}
+        canManage
+        initialStatus={initialStatus}
+        detailHrefBuilder={(id) => `/admin/announcements/${id}`}
+      />
+
+      <Dialog open={createOpen} onOpenChange={handleOpenChange}>
+        <DialogContent className="max-h-[90vh] max-w-2xl overflow-y-auto">
+          <DialogHeader>
+            <DialogTitle>New Announcement</DialogTitle>
+          </DialogHeader>
+          <AnnouncementForm mode="create" grades={grades} classes={classes} />
+        </DialogContent>
+      </Dialog>
+    </div>
+  )
+}