feat: productionize learning engine and classroom

OpenMAIC/lib/makelore-course/immutability.ts

@@ -0,0 +1,34 @@
+import type { CourseRecord } from '@/lib/course-framework/types';
+import { readCourseRecord } from '@/lib/course-framework/store';
+import { readFrozenLearningPackageRecord } from '@/lib/makelore-course/package';
+
+type CoursePublicationState = Pick<CourseRecord, 'publication' | 'externalPublication'>;
+
+/** A frozen course id is a one-shot immutable product identity. */
+export class FrozenLearningCourseMutationError extends Error {
+  constructor(public readonly courseId: string) {
+    super(`课程 ${courseId} 已冻结，不能继续生成或重新生成；如需修改，请新建课程`);
+    this.name = 'FrozenLearningCourseMutationError';
+  }
+}
+
+/**
+ * Enforce the single immutable-course rule at every source mutation boundary.
+ *
+ * The frozen record is authoritative: Works can successfully finalize an
+ * archive and then fail before writing the later external-publication receipt.
+ * Legacy publication receipts remain additional evidence for courses created
+ * before aggregate finalization was introduced.
+ */
+export async function assertLearningCourseMutable(
+  courseId: string,
+  knownRecord?: CoursePublicationState | null,
+): Promise<void> {
+  const [frozen, record] = await Promise.all([
+    readFrozenLearningPackageRecord(courseId),
+    knownRecord === undefined ? readCourseRecord(courseId) : Promise.resolve(knownRecord),
+  ]);
+  if (frozen || record?.publication || record?.externalPublication) {
+    throw new FrozenLearningCourseMutationError(courseId);
+  }
+}