refactor: fix remaining P2 architecture issues

Fix P2-6: proxy.ts now uses Permissions constants instead of hardcoded strings

Fix P2-7: useA11yId file no longer exists (use-aria-live.ts already in hooks/)

Fix P2-8: schema.ts section numbering reordered to continuous 1-24

Fix P2-11: announcements dead code void wasPublished already removed

Fix P2-17: app-sidebar.tsx uses hasRole() instead of permission-based role inference

Fix P2-18: scheduling/actions.ts removes trailing re-export of data-access; 4 pages now import directly from data-access

Sync architecture docs 004 and 005

docs/architecture/005_architecture_data.json

@@ -5,7 +5,7 @@
     "generatedAt": "2026-06-17",
     "formatVersion": "1.1",
     "rule": "每次文件修改后须同步更新本文件",
-    "lastUpdate": "P1-1 已修复：所有跨模块直查已改为通过对方 data-access 接口（homework/grades/parent/diagnostic/elective/proctoring/notifications/scheduling/classes 模块）；exams 模块 getSubjectsAction/getGradesAction 改为调用 school data-access；questions 模块 getKnowledgePointOptionsAction 改为调用 textbooks data-access；grades 模块多处直查 classes/classEnrollments/subjects/users 改为调用对应模块 data-access；classes 模块 actions 直查 grades 表改为调用 school data-access，getSessionTeacherId 改为通过 auth-guard.getAuthContext；attendance 模块 getClassStudentsForAttendance 改为通过 classes data-access；scheduling 模块 autoScheduleAction 直查 users 改为通过 users data-access；notifications 模块 sendClassNotificationAction 直查 classes/classEnrollments 改为通过 classes data-access；proctoring 模块跨模块直查 exams/examSubmissions/users 改为通过 exams/users data-access；diagnostic 模块 updateMasteryFromSubmission 跨模块直查 4 张表改为通过 exams/questions data-access；dashboard 教师仪表盘直查 users 改为通过 users data-access；users 模块 updateUserProfile 绕过 data-access 已下沉；P2-20 已修复：getDemoStudentUser 从 homework 模块迁移至 users 模块 getCurrentStudentUser（homework 保留 re-export 向后兼容），6 个 student 页面（dashboard/assignments/assignments-[assignmentId]/courses/textbooks/textbooks-[id]/schedule）改用 users 模块，消除对 homework 的虚假依赖；student/elective 改用 getAuthContext()；shared/types/action-state.ts 移除分号修复 Prettier 违规；shared/types/permissions.ts EXAM_PROCTOR_READ 字符串从 exam:proctor_read 改为 exam:proctor:read 统一命名；为 ActionState/DataScope/AuthContext 添加 JSDoc 注释；P0-2 已修复：shared/lib ↔ auth 循环依赖已解决，新增 shared/lib/session.ts 单一入口封装 getSession()（dynamic import 打破静态循环），audit-logger/change-logger/auth-guard 改为通过 session.ts 获取 session；P1-6 已修复：http-utils.ts 新增 getUserAgent()，audit-logger/change-logger/login-logger 删除本地重复 IP/UA 提取逻辑，统一复用 resolveClientIp/getUserAgent；P0-1 已修复：exams/data-access.persistAiGeneratedExamDraft 改为调用 questions/data-access.createQuestionWithRelations，不再直查 questions 表；P0-2 已修复：exams/data-access.getExams/getExamById/getExamsDashboardStats 改为调用 classes/data-access.getClassGradeIdsByClassIds，不再直查 classes 表；P1-2 已修复：exams/homework/questions/announcements actions 层 DB 操作下沉到 data-access；P2-2 已修复：ai.ts 拆分为 ai/ 目录；P0-8 已修复：school actions 层 DB 操作下沉到 data-access，logAudit 改为 after() 异步非阻塞；P0-7 已修复：classes/data-access-stats.ts 和 data-access-students.ts 不再直查 homework/exams 表，改为调用新增的 homework/data-access-classes.ts 暴露的 7 个函数；新增 diagnostic/schema.ts（6 个 Zod schema）和 classes/schema.ts（13 个 Zod schema），actions.ts 中手动 typeof 校验全部替换为 Zod safeParse"
+    "lastUpdate": "P2-6/P2-7/P2-8/P2-11/P2-17/P2-18 已修复：proxy.ts 改用 Permissions 常量替代硬编码字符串；useA11yId 文件已不存在（use-aria-live.ts 已在 hooks/ 目录）；schema.ts 分节编号重新编号为连续 1-24，消除 8b/14b/乱序问题；announcements 死代码 void wasPublished 已不存在；layout/app-sidebar.tsx 改用 hasRole() 判断角色，不再用权限反推角色；scheduling/actions.ts 移除末尾 re-export data-access，4 个页面改为从 data-access 直接导入；P1-1 已修复：所有跨模块直查已改为通过对方 data-access 接口（homework/grades/parent/diagnostic/elective/proctoring/notifications/scheduling/classes 模块）；P0-2 已修复：shared/lib ↔ auth 循环依赖已解决，新增 shared/lib/session.ts 单一入口；P1-6 已修复：http-utils.ts 统一 IP/UA 提取；P0-1/P0-2/P0-3/P0-4/P0-5/P0-7/P0-8 已修复；P1-2 已修复：actions 层 DB 操作下沉到 data-access；P2-2/P2-3/P2-12/P2-20 已修复"
   },
   "architectureOverview": {
     "layers": [