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/modules/lesson-preparation/data-access-templates.ts

@@ -0,0 +1,92 @@
+import "server-only";
+
+import { and, eq } from "drizzle-orm";
+import { createId } from "@paralleldrive/cuid2";
+
+import { db } from "@/shared/db";
+import { lessonPlanTemplates, lessonPlans } from "@/shared/db/schema";
+import { SYSTEM_TEMPLATES } from "./constants";
+import { normalizeDocument } from "./data-access";
+import type {
+  LessonPlanTemplate,
+  TemplateBlockSkeleton,
+} from "./types";
+
+export async function getLessonPlanTemplates(
+  userId: string,
+): Promise<LessonPlanTemplate[]> {
+  // system 模板（内存）+ personal 模板（DB）
+  const systemTemplates: LessonPlanTemplate[] = SYSTEM_TEMPLATES.map((t) => ({
+    id: t.id,
+    name: t.name,
+    type: "system",
+    scope: t.scope,
+    blocks: t.blocks,
+    creatorId: null,
+    createdAt: "",
+    updatedAt: "",
+  }));
+
+  const personalRows = await db
+    .select()
+    .from(lessonPlanTemplates)
+    .where(
+      and(
+        eq(lessonPlanTemplates.type, "personal"),
+        eq(lessonPlanTemplates.creatorId, userId),
+      ),
+    );
+  const personalTemplates =
+    personalRows as unknown as LessonPlanTemplate[];
+
+  return [...systemTemplates, ...personalTemplates];
+}
+
+export async function saveAsTemplate(input: {
+  sourcePlanId: string;
+  name: string;
+  userId: string;
+}): Promise<{ templateId: string }> {
+  // 从课案 content 提取 block 骨架
+  const plan = await db
+    .select({ content: lessonPlans.content })
+    .from(lessonPlans)
+    .where(
+      and(
+        eq(lessonPlans.id, input.sourcePlanId),
+        eq(lessonPlans.creatorId, input.userId),
+      ),
+    )
+    .limit(1);
+  if (plan.length === 0) throw new Error("课案不存在或无权访问");
+
+  const doc = normalizeDocument(plan[0].content);
+  const skeleton: TemplateBlockSkeleton[] = doc.nodes.map((b) => ({
+    type: b.type,
+    title: b.title,
+  }));
+
+  const templateId = createId();
+  await db.insert(lessonPlanTemplates).values({
+    id: templateId,
+    name: input.name,
+    type: "personal",
+    scope: "custom",
+    blocks: skeleton,
+    creatorId: input.userId,
+  });
+  return { templateId };
+}
+
+export async function deletePersonalTemplate(
+  templateId: string,
+  userId: string,
+): Promise<void> {
+  await db.delete(lessonPlanTemplates).where(
+    and(
+      eq(lessonPlanTemplates.id, templateId),
+      eq(lessonPlanTemplates.type, "personal"),
+      eq(lessonPlanTemplates.creatorId, userId),
+    ),
+  );
+}