feat(lesson-preparation): add readonly view, anchor node selector, and type guards

- Add lesson-plan-readonly-view for viewing published plans

- Add anchor-node-selector and textbook-segments for canvas anchor positioning

- Add i18n-errors and type-guards lib utilities

- Add lesson-plan-provider-setup for provider initialization

- Update actions, data-access (knowledge, versions, main), publish-service

- Update blocks (blackboard, exercise, homework, import, key-point, objective, reflection)

- Update editor, node-editor, node-edit-panel, pickers, and providers

src/modules/lesson-preparation/publish-service.ts

@@ -10,7 +10,8 @@ import { persistExamDraft, addExamQuestions } from "@/modules/exams/data-access"
 import { createHomeworkAssignment } from "@/modules/homework/data-access-write";
 import { getStudentIdsByClassIds } from "@/modules/classes/data-access";
 import { normalizeDocument } from "./data-access";
-import type { LessonPlanDocument, ExerciseBlockData, LessonPlan, LessonPlanStatus } from "./types";
+import { isExerciseBlockData, isLessonPlanStatus, isValidQuestionType } from "./lib/type-guards";
+import type { LessonPlanDocument, LessonPlan, LessonPlanStatus } from "./types";
 
 interface PublishInput {
   planId: string;
@@ -19,6 +20,10 @@ interface PublishInput {
   classIds: string[];
   availableAt?: Date;
   dueAt?: Date;
+  /** 作业标题（由 actions 层 i18n 翻译后传入）*/
+  homeworkTitle: string;
+  /** 作业描述（由 actions 层 i18n 翻译后传入）*/
+  homeworkDescription: string;
 }
 
 interface PublishResult {
@@ -27,12 +32,6 @@ interface PublishResult {
   updatedContent: LessonPlanDocument;
 }
 
-// 类型守卫：安全地将 string 收窄为 LessonPlanStatus
-const LESSON_PLAN_STATUSES = ["draft", "published", "archived"] as const;
-function isLessonPlanStatus(v: string): v is LessonPlanStatus {
-  return (LESSON_PLAN_STATUSES as readonly string[]).includes(v);
-}
-
 /**
  * publish-service 错误：使用错误码替代硬编码中文，
  * 由 actions 层通过 PUBLISH_ERROR_KEY_MAP 翻译为 i18n 消息。
@@ -44,7 +43,8 @@ export type PublishErrorCode =
   | "NO_QUESTIONS"
   | "ALREADY_PUBLISHED"
   | "NO_SUBJECT_OR_GRADE"
-  | "NO_STUDENTS";
+  | "NO_STUDENTS"
+  | "INVALID_QUESTION_TYPE";
 
 export class PublishServiceError extends Error {
   constructor(public readonly code: PublishErrorCode) {
@@ -64,7 +64,10 @@ export async function publishLessonPlanHomework(
     .limit(1);
   if (rows.length === 0) throw new PublishServiceError("PLAN_NOT_FOUND");
   const row = rows[0];
-  // 类型守卫：从 Drizzle 推导类型收窄为 LessonPlan 所需字段
+  // 使用类型守卫收窄（替代 as 断言）
+  const status: LessonPlanStatus = isLessonPlanStatus(row.status)
+    ? row.status
+    : "draft";
   const plan: LessonPlan = {
     id: row.id,
     title: row.title,
@@ -76,7 +79,7 @@ export async function publishLessonPlanHomework(
     templateId: row.templateId,
     templateName: row.templateName,
     content: normalizeDocument(row.content),
-    status: isLessonPlanStatus(row.status) ? row.status : "draft",
+    status,
     creatorId: row.creatorId,
     lastSavedAt: row.lastSavedAt?.toISOString() ?? null,
     createdAt: row.createdAt.toISOString(),
@@ -85,13 +88,15 @@ export async function publishLessonPlanHomework(
   if (plan.creatorId !== input.userId)
     throw new PublishServiceError("NO_PERMISSION");
 
-  // 2. 定位 exercise block
+  // 2. 定位 exercise block（使用类型守卫替代 as 断言）
   const block = plan.content.nodes.find((b) => b.id === input.blockId);
   if (!block || block.type !== "exercise")
     throw new PublishServiceError("NO_EXERCISE_BLOCK");
-  const data = block.data as ExerciseBlockData;
-  if (data.items.length === 0) throw new PublishServiceError("NO_QUESTIONS");
-  if (data.publishedAssignmentId)
+  if (!isExerciseBlockData(block.data))
+    throw new PublishServiceError("NO_EXERCISE_BLOCK");
+  if (block.data.items.length === 0)
+    throw new PublishServiceError("NO_QUESTIONS");
+  if (block.data.publishedAssignmentId)
     throw new PublishServiceError("ALREADY_PUBLISHED");
 
   // 3. inline 题目入库，替换占位 ID
@@ -99,22 +104,22 @@ export async function publishLessonPlanHomework(
   const newBlock = newContent.nodes.find((b) => b.id === input.blockId);
   if (!newBlock || newBlock.type !== "exercise")
     throw new PublishServiceError("NO_EXERCISE_BLOCK");
-  const newData = newBlock.data as ExerciseBlockData;
+  if (!isExerciseBlockData(newBlock.data))
+    throw new PublishServiceError("NO_EXERCISE_BLOCK");
+  const newData = newBlock.data;
 
   for (let i = 0; i < newData.items.length; i++) {
     const item = newData.items[i];
     if (item.source === "inline" && item.inlineContent) {
-      // 类型守卫：确保 inline 题目类型合法
-      const validTypes = ["single_choice", "multiple_choice", "text", "judgment", "composite"] as const;
       const qt = item.inlineContent.type;
-      if (!validTypes.includes(qt as typeof validTypes[number])) {
-        throw new Error(`无效的题目类型: ${qt}`);
+      // 使用类型守卫校验题目类型（替代 as 断言 + 硬编码中文错误）
+      if (!isValidQuestionType(qt)) {
+        throw new PublishServiceError("INVALID_QUESTION_TYPE");
       }
-      const questionType = qt as typeof validTypes[number];
       const questionId = await createQuestionWithRelations(
         {
           content: item.inlineContent.content,
-          type: questionType,
+          type: qt,
           difficulty: item.inlineContent.difficulty,
           knowledgePointIds: item.inlineContent.knowledgePointIds,
         },
@@ -128,19 +133,19 @@ export async function publishLessonPlanHomework(
     }
   }
 
-  // 4. 打包 exam 草稿
+  // 4. 打包 exam 草稿（标题/描述由 actions 层 i18n 传入）
   const examId = createId();
   if (!plan.subjectId || !plan.gradeId) {
     throw new PublishServiceError("NO_SUBJECT_OR_GRADE");
   }
   await persistExamDraft({
     examId,
-    title: `${plan.title} - 作业`,
+    title: input.homeworkTitle,
     creatorId: input.userId,
     subjectId: plan.subjectId,
     gradeId: plan.gradeId,
     scheduledAt: undefined,
-    description: `来自课案：${plan.title}`,
+    description: input.homeworkDescription,
   });
   // 插入 examQuestions（通过 exams data-access 跨模块接口）
   await addExamQuestions(
@@ -161,8 +166,8 @@ export async function publishLessonPlanHomework(
   await createHomeworkAssignment({
     assignmentId,
     sourceExamId: examId,
-    title: `${plan.title} - 作业`,
-    description: `来自课案：${plan.title}`,
+    title: input.homeworkTitle,
+    description: input.homeworkDescription,
     structure: null,
     status: "published",
     creatorId: input.userId,