feat(portal-shell): error-book + diagnostic + analytics 模块 5 页迁移（教师域 §9.1 B2）

§9.1 line 637-639 教师域：
- /shell/teacher/error-book (列表，1 页)
- /shell/teacher/diagnostic (列表) + /class/[classId] (详情) — 2 页
- /shell/teacher/analytics (概览) + /[studentId] (详情) — 2 页
契约：
- error-book ✅ 真实 errorBookItems/errorBookStats
- diagnostic ✅ 真实 diagnosticReports 列表 + 详情 ❌ MSW
- analytics 🟡 真实 learningTrend/studentWeakness + 概览 ❌ MSW

新增文件（24 个）：
- src/lib/api/{error-book,diagnostic,analytics}.ts (hooks)
- src/lib/api/operations/{error-book,diagnostic,analytics}.graphql.ts (documents)
- src/features/teacher/{error-book,diagnostic,analytics}/ (clients + transformations + tests)
- src/app/shell/teacher/{error-book,diagnostic,analytics}/ (5 page.tsx + 3 loading + 3 error)

修改文件（7 个）：
- src/mocks/graphql-data.ts (7 handler cases)
- src/messages/{zh-CN,en}.json (errorBook/diagnostic/analytics i18n)
- src/lib/api/{index,operations/index}.ts (导出)
- src/shared/lib/route-permissions.ts (3 EXACT + 3 PREFIX 路由权限)
- scripts/check-page-count.ts (baseline 53 → 58)

DoD 验收（§11.3 11 项）：
- typecheck 0 errors
- lint 0 errors
- vitest 734 tests passed
- lint:tokens 0 errors
- check:pages 58 PASS
- route-permissions 已声明
- 三态齐备
- @contract-pending + MSW 兜底（仅对 schema 不存在的字段）
- i18n zh-CN + en 同步

设计决策：
- 类型命名冲突解决：ErrorBookItem → ErrorBookEntry；ErrorBookStats → TeacherErrorBookStats；
  KnowledgePointErrorStats → ErrorBookKpStats；useErrorBookStats → useTeacherErrorBookStats
  （避免与 dashboard.ts/student.ts 同名类型冲突）
- analytics TrendPoint/WeakPoint 形状相同，从 dashboard.ts import 复用
- error-book/analytics 复用 CLASS_READ/CLASS_MANAGE（无专用教师权限点）；
  diagnostic 复用 DIAGNOSTIC_READ/DIAGNOSTIC_MANAGE

关联：ARCHITECTURE.md §5.3 / §5.4 / §5.5 / §9.1 / §10 P2 / §11.3 / §11.4
契约工单：docs/architecture/issues/contracts/core-edu_contract.md

apps/portal-shell/scripts/check-page-count.ts

@@ -19,10 +19,10 @@ interface Baseline {
   categories: Record<string, { pattern: string; min: number; label: string }>;
 }
 
-// Baseline as of P2 B2 (2026-07-22, course-plans + elective modules added).
+// Baseline as of P2 B3 (2026-07-22, error-book + diagnostic + analytics modules added).
 // Update when adding pages.
 const BASELINE: Baseline = {
-  total: 53,
+  total: 58,
   categories: {
     dashboards: {
       pattern: "shell/{admin,teacher,student,parent}/page.tsx",