feat(lesson-preparation): major update with AI features, schedules, and new components

- Add actions-schedules.ts and data-access-schedules.ts for schedule management

- Add AI differentiation, AI feedback, consistency check dialogs

- Add attachment-picker, curriculum-heatmap, print-view, version-diff-view

- Add lesson-plan-mobile-view and schedule-dialog components

- Add lib: ai-differentiation, ai-feedback, auto-layout, consistency-check,

  curriculum-coverage, export, version-diff

- Add history-slice hook for version history

- Update existing components, hooks, providers, services, types

- Add teacher lesson-plans heatmap and library pages

src/app/(dashboard)/teacher/lesson-plans/heatmap/page.tsx

@@ -0,0 +1,124 @@
+import type { JSX } from "react";
+import { BookOpen } from "lucide-react";
+import { getTranslations } from "next-intl/server";
+import { requirePermission } from "@/shared/lib/auth-guard";
+import { Permissions } from "@/shared/types/permissions";
+import { getLessonPlans } from "@/modules/lesson-preparation/data-access";
+import { getLessonPlanById } from "@/modules/lesson-preparation/data-access";
+import { getKnowledgePointsByTextbookId, getTextbooks } from "@/modules/textbooks/data-access";
+import { CurriculumHeatmap } from "@/modules/lesson-preparation/components/curriculum-heatmap";
+import type { PlanKpLink } from "@/modules/lesson-preparation/lib/curriculum-coverage";
+import type { LessonPlanDocument } from "@/modules/lesson-preparation/types";
+import { isRecord } from "@/shared/lib/type-guards";
+import { EmptyState } from "@/shared/components/ui/empty-state";
+
+export const dynamic = "force-dynamic";
+
+/**
+ * V5-20 T4：教师端课标热力图页面。
+ *
+ * 展示教师所有课案对所选教材知识点的覆盖情况。
+ * 从教师所有课案中提取 knowledgePointIds，统计覆盖率。
+ */
+export default async function HeatmapPage(): Promise<JSX.Element> {
+  const t = await getTranslations("lessonPreparation");
+  const ctx = await requirePermission(Permissions.LESSON_PLAN_READ);
+
+  // 教师所有课案（含草稿和已发布）
+  const [plans, textbooks] = await Promise.all([
+    getLessonPlans({}, ctx.dataScope, ctx.userId),
+    getTextbooks(),
+  ]);
+
+  // 仅保留有教材的课案
+  const plansWithTextbook = plans.filter((p) => p.textbookId);
+
+  // 默认展示教师第一本教材（按使用频率）
+  const textbookCounts = new Map<string, number>();
+  for (const p of plansWithTextbook) {
+    if (p.textbookId) {
+      textbookCounts.set(p.textbookId, (textbookCounts.get(p.textbookId) ?? 0) + 1);
+    }
+  }
+  const defaultTextbookId =
+    [...textbookCounts.entries()].sort((a, b) => b[1] - a[1])[0]?.[0] ?? textbooks[0]?.id ?? "";
+
+  if (!defaultTextbookId || textbooks.length === 0) {
+    return (
+      <div className="p-6">
+        <EmptyState
+          icon={BookOpen}
+          title={t("heatmap.title")}
+          description={t("heatmap.selectTextbook")}
+          className="border-none shadow-none"
+        />
+      </div>
+    );
+  }
+
+  // 获取该教材的所有知识点
+  const allKps = await getKnowledgePointsByTextbookId(defaultTextbookId);
+
+  // 提取该教材下所有课案的知识点关联
+  const planLinks: PlanKpLink[] = [];
+  const chapterNames: Record<string, string> = {};
+  for (const plan of plansWithTextbook.filter((p) => p.textbookId === defaultTextbookId)) {
+    try {
+      const fullPlan = await getLessonPlanById(plan.id, ctx.userId);
+      if (!fullPlan) continue;
+      const doc = fullPlan.content as LessonPlanDocument;
+      const kpSet = new Set<string>();
+      for (const node of doc.nodes) {
+        if (!isRecord(node.data)) continue;
+        const dataKps = (node.data as { knowledgePointIds?: unknown }).knowledgePointIds;
+        if (Array.isArray(dataKps)) {
+          for (const kp of dataKps) {
+            if (typeof kp === "string") kpSet.add(kp);
+          }
+        }
+      }
+      if (kpSet.size > 0) {
+        planLinks.push({ planId: plan.id, knowledgePointIds: [...kpSet] });
+      }
+    } catch {
+      // 单个课案加载失败不阻塞整体
+    }
+  }
+
+  // 章节名映射（从 textbooks 模块获取）
+  // 此处简化：使用知识点自身的 chapterId，章节名从 textbooks data-access 获取
+  // 为避免 N+1 查询，此处仅用 chapterId 作为 key，章节名由前端未知章节兜底
+  // 完整实现可在 textbooks data-access 添加批量查询函数
+  for (const kp of allKps) {
+    if (kp.chapterId) {
+      chapterNames[kp.chapterId] = kp.chapterId; // 占位，实际应查询章节名
+    }
+  }
+
+  return (
+    <div className="p-6 space-y-4">
+      <div>
+        <h1 className="text-2xl font-bold tracking-tight flex items-center gap-2">
+          <BookOpen className="h-6 w-6" aria-hidden="true" />
+          {t("heatmap.title")}
+        </h1>
+        <p className="text-muted-foreground">{t("heatmap.description")}</p>
+      </div>
+
+      {allKps.length === 0 ? (
+        <EmptyState
+          icon={BookOpen}
+          title={t("heatmap.noData")}
+          description={t("heatmap.description")}
+          className="border-none shadow-none"
+        />
+      ) : (
+        <CurriculumHeatmap
+          allKps={allKps}
+          planLinks={planLinks}
+          chapterNames={chapterNames}
+        />
+      )}
+    </div>
+  );
+}