refactor(announcements,messaging,notifications): V1+V2 审计重构 — i18n 命名空间独立 + 通知标题 i18n 化 + 服务端过滤 + 编排下沉 + 表单错误展示 + 架构图同步

V1 改进（已完成）:
- P0-4/P1-4/P1-5: 通知组件和 CRUD Action 从 messaging 迁移至 notifications 模块
- P1-5: 新增 getMessagesPageData / getAdminAnnouncementsPageData 编排函数
- P1-6: announcements schema 添加 superRefine 条件校验
- P1-7: 新增 useMessageSearch hook（防抖 + 请求竞态取消）+ 客户端分页 UI
- P1-9: deleteMessage 事务化
- P2-11: 全模块 trackEvent 埋点
- 全模块 i18n 接入 + Error Boundary + a11y 改进

V2 改进（本次完成）:
- V2-P0-1: 通知 i18n 命名空间独立（notifications.json），useTranslations 从 "messages" 切换到 "notifications"
- V2-P0-2: 公告/消息通知标题 i18n 化，Server Action 中使用 getTranslations 生成通知标题
- V2-P1-1: AnnouncementList 纯服务端过滤，移除客户端 useState/useMemo
- V2-P1-2: MessageList 客户端过滤仅在初始数据时执行，搜索结果由服务端按 tab 过滤
- V2-P1-3: 消息详情页编排下沉，新增 getMessageDetailPageData 编排函数
- V2-P1-4: 表单服务端校验错误展示（fieldErrors + aria-invalid）
- V2-P2-1: 轮询间隔常量化（POLL_INTERVAL_MS）
- V2-P2-2: 架构图同步（004 + 005）

src/modules/layout/config/navigation.ts

@@ -36,6 +36,26 @@ export type NavItem = {
   items?: { title: string; href: string; permission?: Permission }[]
 }
 
+/**
+ * 公共导航项：所有已登录用户均可访问的功能模块。
+ * 通过权限点（permission）控制可见性，新增角色只需在 NAV_CONFIG 中引用这些公共项，
+ * 无需复制粘贴。符合"配置驱动设计"和"严禁 role === 'xxx' 硬编码"的规则。
+ */
+const COMMON_NAV_ITEMS: NavItem[] = [
+  {
+    title: "Announcements",
+    icon: Megaphone,
+    href: "/announcements",
+    permission: Permissions.ANNOUNCEMENT_READ,
+  },
+  {
+    title: "Messages",
+    icon: Mail,
+    href: "/messages",
+    permission: Permissions.MESSAGE_READ,
+  },
+]
+
 export const NAV_CONFIG: Partial<Record<Role, NavItem[]>> = {
   admin: [
     {
@@ -118,12 +138,7 @@ export const NAV_CONFIG: Partial<Record<Role, NavItem[]>> = {
         { title: "Data Changes", href: "/admin/audit-logs/data-changes" },
       ]
     },
-    {
-      title: "Messages",
-      icon: Mail,
-      href: "/messages",
-      permission: Permissions.MESSAGE_READ,
-    },
+    ...COMMON_NAV_ITEMS,
     {
       title: "Settings",
       icon: Settings,
@@ -243,18 +258,85 @@ export const NAV_CONFIG: Partial<Record<Role, NavItem[]>> = {
         { title: "年级洞察", href: "/management/grade/insights" },
       ]
     },
+    ...COMMON_NAV_ITEMS,
+  ],
+  grade_head: [
     {
-      title: "公告",
-      icon: Megaphone,
-      href: "/announcements",
-      permission: Permissions.ANNOUNCEMENT_READ,
+      title: "仪表盘",
+      icon: LayoutDashboard,
+      href: "/management",
+      permission: Permissions.GRADE_MANAGE,
     },
     {
-      title: "消息",
-      icon: Mail,
-      href: "/messages",
-      permission: Permissions.MESSAGE_READ,
+      title: "年级管理",
+      icon: Briefcase,
+      href: "/management",
+      permission: Permissions.GRADE_MANAGE,
+      items: [
+        { title: "年级班级", href: "/management/grade/classes" },
+        { title: "年级洞察", href: "/management/grade/insights" },
+      ]
     },
+    {
+      title: "考勤",
+      icon: CalendarCheck,
+      href: "/teacher/attendance",
+      permission: Permissions.ATTENDANCE_READ,
+      items: [
+        { title: "考勤记录", href: "/teacher/attendance" },
+        { title: "考勤统计", href: "/teacher/attendance/stats", permission: Permissions.ATTENDANCE_READ },
+      ]
+    },
+    {
+      title: "成绩",
+      icon: GraduationCap,
+      href: "/teacher/grades",
+      permission: Permissions.GRADE_RECORD_READ,
+      items: [
+        { title: "成绩统计", href: "/teacher/grades/stats", permission: Permissions.GRADE_RECORD_READ },
+        { title: "成绩分析", href: "/teacher/grades/analytics", permission: Permissions.GRADE_RECORD_READ },
+      ]
+    },
+    ...COMMON_NAV_ITEMS,
+  ],
+  teaching_head: [
+    {
+      title: "仪表盘",
+      icon: LayoutDashboard,
+      href: "/management",
+      permission: Permissions.GRADE_MANAGE,
+    },
+    {
+      title: "年级管理",
+      icon: Briefcase,
+      href: "/management",
+      permission: Permissions.GRADE_MANAGE,
+      items: [
+        { title: "年级班级", href: "/management/grade/classes" },
+        { title: "年级洞察", href: "/management/grade/insights" },
+      ]
+    },
+    {
+      title: "考勤",
+      icon: CalendarCheck,
+      href: "/teacher/attendance",
+      permission: Permissions.ATTENDANCE_READ,
+      items: [
+        { title: "考勤记录", href: "/teacher/attendance" },
+        { title: "考勤统计", href: "/teacher/attendance/stats", permission: Permissions.ATTENDANCE_READ },
+      ]
+    },
+    {
+      title: "成绩",
+      icon: GraduationCap,
+      href: "/teacher/grades",
+      permission: Permissions.GRADE_RECORD_READ,
+      items: [
+        { title: "成绩统计", href: "/teacher/grades/stats", permission: Permissions.GRADE_RECORD_READ },
+        { title: "成绩分析", href: "/teacher/grades/analytics", permission: Permissions.GRADE_RECORD_READ },
+      ]
+    },
+    ...COMMON_NAV_ITEMS,
   ],
   student: [
     {
@@ -303,18 +385,7 @@ export const NAV_CONFIG: Partial<Record<Role, NavItem[]>> = {
       href: "/student/elective",
       permission: Permissions.ELECTIVE_SELECT,
     },
-    {
-      title: "Announcements",
-      icon: Megaphone,
-      href: "/announcements",
-      permission: Permissions.ANNOUNCEMENT_READ,
-    },
-    {
-      title: "Messages",
-      icon: Mail,
-      href: "/messages",
-      permission: Permissions.MESSAGE_READ,
-    },
+    ...COMMON_NAV_ITEMS,
   ],
   parent: [
     {
@@ -339,17 +410,6 @@ export const NAV_CONFIG: Partial<Record<Role, NavItem[]>> = {
       icon: CalendarRange,
       href: "/parent/leave",
     },
-    {
-      title: "Announcements",
-      icon: Megaphone,
-      href: "/announcements",
-      permission: Permissions.ANNOUNCEMENT_READ,
-    },
-    {
-      title: "Messages",
-      icon: Mail,
-      href: "/messages",
-      permission: Permissions.MESSAGE_READ,
-    },
+    ...COMMON_NAV_ITEMS,
   ]
 }