feat(lesson-preparation): add anchor canvas design, new blocks, and textbook content node

- Add anchor injector for canvas-based anchor positioning

- Add new block components: blackboard, homework, import, key-point, new-teaching, objective, summary

- Add textbook content node for React Flow canvas

- Update actions (kp, publish, main), data-access (templates, versions, main)

- Update editor, node-editor, block-renderer, and picker components

- Update schema, types, hooks, and lib utilities (document-migration, node-summary, rf-mappers)

src/modules/lesson-preparation/data-access-versions.ts

@@ -60,23 +60,25 @@ export async function createLessonPlanVersion(input: {
   isAuto: boolean;
   label?: string;
 }): Promise<{ versionNo: number }> {
-  // 取当前最大 versionNo
-  const maxRow = await db
-    .select({ maxNo: max(lessonPlanVersions.versionNo) })
-    .from(lessonPlanVersions)
-    .where(eq(lessonPlanVersions.planId, input.planId));
-  const nextNo = (maxRow[0]?.maxNo ?? 0) + 1;
+  // P0 修复：max(versionNo)+1 必须在事务内完成，避免并发产生重复版本号
+  return await db.transaction(async (tx) => {
+    const maxRow = await tx
+      .select({ maxNo: max(lessonPlanVersions.versionNo) })
+      .from(lessonPlanVersions)
+      .where(eq(lessonPlanVersions.planId, input.planId));
+    const nextNo = (maxRow[0]?.maxNo ?? 0) + 1;
 
-  await db.insert(lessonPlanVersions).values({
-    id: createId(),
-    planId: input.planId,
-    versionNo: nextNo,
-    label: input.label ?? null,
-    content: input.content,
-    isAuto: input.isAuto,
-    creatorId: input.userId,
+    await tx.insert(lessonPlanVersions).values({
+      id: createId(),
+      planId: input.planId,
+      versionNo: nextNo,
+      label: input.label ?? null,
+      content: input.content,
+      isAuto: input.isAuto,
+      creatorId: input.userId,
+    });
+    return { versionNo: nextNo };
   });
-  return { versionNo: nextNo };
 }
 
 export async function getVersionContent(
@@ -116,22 +118,33 @@ export async function revertToVersion(
   const content = await getVersionContent(planId, versionNo, userId);
   if (!content) return null;
 
-  // 用该版本 content 覆盖当前 + 生成新版本
-  await db
-    .update(lessonPlans)
-    .set({ content, lastSavedAt: new Date() })
-    .where(
-      and(eq(lessonPlans.id, planId), eq(lessonPlans.creatorId, userId)),
-    );
+  // P0 修复：update 与 createLessonPlanVersion 必须在同一事务内，
+  // 避免回退后 content 已覆盖但版本记录未生成的不一致状态
+  return await db.transaction(async (tx) => {
+    await tx
+      .update(lessonPlans)
+      .set({ content, lastSavedAt: new Date() })
+      .where(
+        and(eq(lessonPlans.id, planId), eq(lessonPlans.creatorId, userId)),
+      );
 
-  const { versionNo: newNo } = await createLessonPlanVersion({
-    planId,
-    content,
-    userId,
-    isAuto: false,
-    label: `回退到 v${versionNo}`,
+    const maxRow = await tx
+      .select({ maxNo: max(lessonPlanVersions.versionNo) })
+      .from(lessonPlanVersions)
+      .where(eq(lessonPlanVersions.planId, planId));
+    const newNo = (maxRow[0]?.maxNo ?? 0) + 1;
+
+    await tx.insert(lessonPlanVersions).values({
+      id: createId(),
+      planId,
+      versionNo: newNo,
+      label: `回退到 v${versionNo}`,
+      content,
+      isAuto: false,
+      creatorId: userId,
+    });
+    return { newVersionNo: newNo };
   });
-  return { newVersionNo: newNo };
 }
 
 export async function pruneAutoVersions(