chore: establish learning module baseline

OpenMAIC/app/api/learn/courses/route.ts

@@ -0,0 +1,34 @@
+// Large-course mode API — learner-facing course manifest list (L2, public read).
+//
+//   GET /api/learn/courses?limit=N
+
+import { type NextRequest } from 'next/server';
+import { apiError, apiSuccess, API_ERROR_CODES } from '@/lib/server/api-response';
+import { createLogger } from '@/lib/logger';
+import { courseManifestRepo } from '@/lib/course-manifest-repo/store';
+import { isPinnedCourseManifestModule } from '@/lib/course-manifest-repo/types';
+
+const log = createLogger('Learner Courses API');
+
+export async function GET(request: NextRequest) {
+  try {
+    const limitParam = Number(new URL(request.url).searchParams.get('limit') ?? 50);
+    const limit = Number.isFinite(limitParam) && limitParam > 0 ? Math.min(limitParam, 100) : 50;
+    const records = (await courseManifestRepo.listRecords(limit)).filter(
+      (record) => record.schemaVersion === 2 && record.modules.every(isPinnedCourseManifestModule),
+    );
+    return apiSuccess({
+      items: records.map((record) => ({
+        courseId: record.courseId,
+        version: record.version,
+        title: record.title,
+        summary: record.summary,
+        moduleCount: record.modules.length,
+        publishedAt: record.publishedAt,
+      })),
+    });
+  } catch (error) {
+    log.error('Learner course listing failed:', error);
+    return apiError(API_ERROR_CODES.INTERNAL_ERROR, 500, 'Failed to list courses');
+  }
+}