refactor(school,classes): 完成 school/grade/class 审计全量改进项

P0-1/P0-2: 删除 grade-management 死模块，年级 CRUD 统一由 school 模块负责

P0-3: classes/actions.ts 从 974 行拆分为 6 个职责文件 + barrel re-export

P0-5: 13 个页面 i18n 全量接入（grades/departments/academic-year/classes/insights）

P1-1: 角色硬编码改为 hasAdminScope/hasTeacherScope/hasStudentScope 基于 dataScope.type

P1-3: 新增 SchoolErrorBoundary + SchoolListSkeleton/SchoolCardSkeleton，4 个页面包裹 Error Boundary

P1-4: classes/types.ts 跨领域类型添加归属决策注释

P1-5: schools-view.tsx 拆分为组合模式（SchoolFormDialog + SchoolDeleteDialog + SchoolListToolbar）

P1-6: 新增 getSchoolsForUser/getGradesForUser 权限感知查询函数

P2-1: 抽取 useSchoolData hook，对话框状态管理与 UI 分离

同步更新架构图文档 004/005

src/app/(dashboard)/admin/school/academic-year/page.tsx

@@ -1,28 +1,36 @@
-import type { Metadata } from "next"
+import type { Metadata } from "next"
 import type { JSX } from "react"
 
+import { getTranslations } from "next-intl/server"
 import { requirePermission } from "@/shared/lib/auth-guard"
 import { Permissions } from "@/shared/types/permissions"
 import { AcademicYearClient } from "@/modules/school/components/academic-year-view"
+import { SchoolErrorBoundary } from "@/modules/school/components/school-error-boundary"
 import { getAcademicYears } from "@/modules/school/data-access"
 
-export const metadata: Metadata = {
-  title: "学年管理 - Next_Edu",
-  description: "管理学年区间与当前激活学年",
-}
-
 export const dynamic = "force-dynamic"
 
+export async function generateMetadata(): Promise<Metadata> {
+  const t = await getTranslations("school")
+  return {
+    title: `${t("academicYear.title")} - Next_Edu`,
+    description: t("academicYear.description"),
+  }
+}
+
 export default async function AdminAcademicYearPage(): Promise<JSX.Element> {
   await requirePermission(Permissions.SCHOOL_MANAGE)
+  const t = await getTranslations("school")
   const years = await getAcademicYears()
   return (
     <div className="flex h-full flex-col space-y-8 p-8">
       <div className="space-y-1">
-        <h2 className="text-2xl font-bold tracking-tight">学年管理</h2>
-        <p className="text-muted-foreground">管理学年区间与当前激活学年。</p>
+        <h2 className="text-2xl font-bold tracking-tight">{t("academicYear.title")}</h2>
+        <p className="text-muted-foreground">{t("academicYear.description")}</p>
       </div>
-      <AcademicYearClient years={years} />
+      <SchoolErrorBoundary>
+        <AcademicYearClient years={years} />
+      </SchoolErrorBoundary>
     </div>
   )
 }

src/app/(dashboard)/admin/school/classes/page.tsx

@@ -1,21 +1,26 @@
 import type { Metadata } from "next"
 import type { JSX } from "react"
 
+import { getTranslations } from "next-intl/server"
 import { requirePermission } from "@/shared/lib/auth-guard"
 import { Permissions } from "@/shared/types/permissions"
 import { getAdminClasses, getTeacherOptions } from "@/modules/classes/data-access"
 import { getGrades, getSchools } from "@/modules/school/data-access"
 import { AdminClassesClient } from "@/modules/classes/components/admin-classes-view"
 
-export const metadata: Metadata = {
-  title: "班级管理 - Next_Edu",
-  description: "管理班级并分配教师",
-}
-
 export const dynamic = "force-dynamic"
 
+export async function generateMetadata(): Promise<Metadata> {
+  const t = await getTranslations("school")
+  return {
+    title: `${t("classManagement.title")} - Next_Edu`,
+    description: t("classManagement.description"),
+  }
+}
+
 export default async function AdminSchoolClassesPage(): Promise<JSX.Element> {
   await requirePermission(Permissions.SCHOOL_MANAGE)
+  const t = await getTranslations("school")
   const [classes, teachers, schools, grades] = await Promise.all([
     getAdminClasses(),
     getTeacherOptions(),
@@ -26,8 +31,8 @@ export default async function AdminSchoolClassesPage(): Promise<JSX.Element> {
   return (
     <div className="flex h-full flex-col space-y-8 p-8">
       <div className="space-y-1">
-        <h2 className="text-2xl font-bold tracking-tight">班级管理</h2>
-        <p className="text-muted-foreground">管理班级并分配教师。</p>
+        <h2 className="text-2xl font-bold tracking-tight">{t("classManagement.title")}</h2>
+        <p className="text-muted-foreground">{t("classManagement.description")}</p>
       </div>
       <AdminClassesClient classes={classes} teachers={teachers} schools={schools} grades={grades} />
     </div>

src/app/(dashboard)/admin/school/departments/page.tsx

@@ -1,28 +1,36 @@
-import type { Metadata } from "next"
+import type { Metadata } from "next"
 import type { JSX } from "react"
 
+import { getTranslations } from "next-intl/server"
 import { requirePermission } from "@/shared/lib/auth-guard"
 import { Permissions } from "@/shared/types/permissions"
 import { DepartmentsClient } from "@/modules/school/components/departments-view"
+import { SchoolErrorBoundary } from "@/modules/school/components/school-error-boundary"
 import { getDepartments } from "@/modules/school/data-access"
 
-export const metadata: Metadata = {
-  title: "部门管理 - Next_Edu",
-  description: "管理学校部门",
-}
-
 export const dynamic = "force-dynamic"
 
+export async function generateMetadata(): Promise<Metadata> {
+  const t = await getTranslations("school")
+  return {
+    title: `${t("departments.title")} - Next_Edu`,
+    description: t("departments.description"),
+  }
+}
+
 export default async function AdminDepartmentsPage(): Promise<JSX.Element> {
   await requirePermission(Permissions.SCHOOL_MANAGE)
+  const t = await getTranslations("school")
   const departments = await getDepartments()
   return (
     <div className="flex h-full flex-col space-y-8 p-8">
       <div className="space-y-1">
-        <h2 className="text-2xl font-bold tracking-tight">部门管理</h2>
-        <p className="text-muted-foreground">管理学校部门。</p>
+        <h2 className="text-2xl font-bold tracking-tight">{t("departments.title")}</h2>
+        <p className="text-muted-foreground">{t("departments.description")}</p>
       </div>
-      <DepartmentsClient departments={departments} />
+      <SchoolErrorBoundary>
+        <DepartmentsClient departments={departments} />
+      </SchoolErrorBoundary>
     </div>
   )
 }

src/app/(dashboard)/admin/school/grades/page.tsx

@@ -1,29 +1,37 @@
-import type { Metadata } from "next"
+import type { Metadata } from "next"
 import type { JSX } from "react"
 
+import { getTranslations } from "next-intl/server"
 import { requirePermission } from "@/shared/lib/auth-guard"
 import { Permissions } from "@/shared/types/permissions"
 import { GradesClient } from "@/modules/school/components/grades-view"
+import { SchoolErrorBoundary } from "@/modules/school/components/school-error-boundary"
 import { getGrades, getSchools, getStaffOptions } from "@/modules/school/data-access"
 
-export const metadata: Metadata = {
-  title: "年级管理 - Next_Edu",
-  description: "管理年级并分配年级组长",
-}
-
 export const dynamic = "force-dynamic"
 
+export async function generateMetadata(): Promise<Metadata> {
+  const t = await getTranslations("school")
+  return {
+    title: `${t("grades.title")} - Next_Edu`,
+    description: t("grades.description"),
+  }
+}
+
 export default async function AdminGradesPage(): Promise<JSX.Element> {
   await requirePermission(Permissions.SCHOOL_MANAGE)
+  const t = await getTranslations("school")
   const [grades, schools, staff] = await Promise.all([getGrades(), getSchools(), getStaffOptions()])
 
   return (
     <div className="flex h-full flex-col space-y-8 p-8">
       <div className="space-y-1">
-        <h2 className="text-2xl font-bold tracking-tight">年级管理</h2>
-        <p className="text-muted-foreground">管理年级并分配年级组长。</p>
+        <h2 className="text-2xl font-bold tracking-tight">{t("grades.title")}</h2>
+        <p className="text-muted-foreground">{t("grades.description")}</p>
       </div>
-      <GradesClient grades={grades} schools={schools} staff={staff} />
+      <SchoolErrorBoundary>
+        <GradesClient grades={grades} schools={schools} staff={staff} />
+      </SchoolErrorBoundary>
     </div>
   )
 }

src/app/(dashboard)/admin/school/schools/page.tsx

@@ -5,6 +5,7 @@ import { getTranslations } from "next-intl/server"
 import { requirePermission } from "@/shared/lib/auth-guard"
 import { Permissions } from "@/shared/types/permissions"
 import { SchoolsClient } from "@/modules/school/components/schools-view"
+import { SchoolErrorBoundary } from "@/modules/school/components/school-error-boundary"
 import { getSchools } from "@/modules/school/data-access"
 
 export const dynamic = "force-dynamic"
@@ -27,7 +28,9 @@ export default async function AdminSchoolsPage(): Promise<JSX.Element> {
         <h2 className="text-2xl font-bold tracking-tight">{t("schools.title")}</h2>
         <p className="text-muted-foreground">{t("schools.description")}</p>
       </div>
-      <SchoolsClient schools={schools} />
+      <SchoolErrorBoundary>
+        <SchoolsClient schools={schools} />
+      </SchoolErrorBoundary>
     </div>
   )
 }