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/textbooks/[id]/loading.tsx

@@ -1,5 +1,5 @@
-import { Skeleton } from "@/shared/components/ui/skeleton";
-import { Separator } from "@/shared/components/ui/separator";
+import { Skeleton } from "@/shared/components/ui/skeleton"
+import { Separator } from "@/shared/components/ui/separator"
 
 export default function Loading() {
   return (
@@ -24,43 +24,43 @@ export default function Loading() {
             <Skeleton className="h-6 w-40" />
             <Skeleton className="h-8 w-24" />
           </div>
-          
+
           <div className="rounded-lg border bg-card p-6 space-y-4">
-             {Array.from({ length: 5 }).map((_, i) => (
-                <div key={i} className="flex items-center gap-4">
-                    <Skeleton className="h-6 w-6 rounded-md" />
-                    <Skeleton className="h-6 w-full rounded-md" />
-                </div>
-             ))}
+            {Array.from({ length: 5 }).map((_, i) => (
+              <div key={i} className="flex items-center gap-4">
+                <Skeleton className="h-6 w-6 rounded-md" />
+                <Skeleton className="h-6 w-full rounded-md" />
+              </div>
+            ))}
           </div>
         </div>
 
         {/* Sidebar Skeleton */}
         <div className="space-y-6">
           <div className="rounded-lg border bg-card p-6 space-y-4">
-             <Skeleton className="h-6 w-32 mb-4" />
-             <div className="space-y-2">
-                <Skeleton className="h-4 w-16" />
-                <Skeleton className="h-5 w-32" />
-             </div>
-             <div className="space-y-2">
-                <Skeleton className="h-4 w-20" />
-                <Skeleton className="h-20 w-full" />
-             </div>
-             <Separator />
-             <div className="grid grid-cols-2 gap-4">
-                <div className="space-y-2">
-                    <Skeleton className="h-3 w-12" />
-                    <Skeleton className="h-4 w-24" />
-                </div>
-                <div className="space-y-2">
-                    <Skeleton className="h-3 w-12" />
-                    <Skeleton className="h-4 w-24" />
-                </div>
-             </div>
+            <Skeleton className="h-6 w-32 mb-4" />
+            <div className="space-y-2">
+              <Skeleton className="h-4 w-16" />
+              <Skeleton className="h-5 w-32" />
+            </div>
+            <div className="space-y-2">
+              <Skeleton className="h-4 w-20" />
+              <Skeleton className="h-20 w-full" />
+            </div>
+            <Separator />
+            <div className="grid grid-cols-2 gap-4">
+              <div className="space-y-2">
+                <Skeleton className="h-3 w-12" />
+                <Skeleton className="h-4 w-24" />
+              </div>
+              <div className="space-y-2">
+                <Skeleton className="h-3 w-12" />
+                <Skeleton className="h-4 w-24" />
+              </div>
+            </div>
           </div>
         </div>
       </div>
     </div>
-  );
+  )
 }