feat: 新增备课模块并修复全模块 P0/P1/P2 缺陷

主要变更:

- 新增 lesson-preparation 模块: 备课编辑器、节点编辑、AI 建议、知识点选择、版本历史、作业发布

- 新增 shared 通用组件: charts/question-bank-filters/schedule-list/ui (chip-nav/filter-bar/page-header/stat-card/stat-item)

- 新增 student/admin 端 loading.tsx 与 error.tsx, 优化加载与错误态体验

- 新增 teacher/lesson-plans 页面 (列表/新建/编辑)

- 新增 drizzle 迁移 0002_tiny_lionheart 及 snapshot

- 新增 textbooks/schema.ts 与 exams/utils/normalize-structure.ts

- 修复 Tiptap v3 SSR hydration 崩溃 (rich-text-block immediatelyRender: false)

- 重构多模块 data-access/actions/组件, 修复权限校验与类型规范

- 同步架构文档 004/005 反映新增模块、导出、依赖关系

- 归档 bugs/* 测试报告与 e2e 测试脚本 (admin/parent/student/teacher web_test)

src/app/(dashboard)/teacher/lesson-plans/[planId]/edit/page.tsx

@@ -0,0 +1,38 @@
+import type { JSX } from "react"
+import { notFound } from "next/navigation"
+import { getLessonPlanById } from "@/modules/lesson-preparation/data-access"
+import { LessonPlanEditor } from "@/modules/lesson-preparation/components/lesson-plan-editor"
+import { getTeacherClasses } from "@/modules/classes/data-access"
+import { getAuthContext } from "@/shared/lib/auth-guard"
+
+export const dynamic = "force-dynamic"
+
+export default async function EditLessonPlanPage({
+  params,
+}: {
+  params: Promise<{ planId: string }>
+}): Promise<JSX.Element> {
+  const { planId } = await params
+  const ctx = await getAuthContext()
+
+  const [plan, teacherClasses] = await Promise.all([
+    getLessonPlanById(planId, ctx.userId),
+    getTeacherClasses({ teacherId: ctx.userId }),
+  ])
+  if (!plan) notFound()
+
+  const classes = teacherClasses.map((c) => ({ id: c.id, name: c.name }))
+
+  return (
+    <div className="h-[calc(100vh-4rem)]">
+      <LessonPlanEditor
+        planId={plan.id}
+        initialTitle={plan.title}
+        initialDoc={plan.content}
+        textbookId={plan.textbookId ?? undefined}
+        chapterId={plan.chapterId ?? undefined}
+        classes={classes}
+      />
+    </div>
+  )
+}