feat: add course catalog, enrollment, progress tracking, quizzes, and reviews

Backend changes:
- Add Enrollment and LessonProgress models to track user progress
- Add UserRole enum (USER, MODERATOR, ADMIN)
- Add course verification and moderation fields
- New CatalogModule: public course browsing, publishing, verification
- New EnrollmentModule: enroll, progress tracking, quiz submission, reviews
- Add quiz generation endpoint to LessonsController

Frontend changes:
- Redesign course viewer: proper course UI with lesson navigation, progress bar
- Add beautiful typography styles for course content (prose-course)
- Fix first-login bug with token exchange retry logic
- New pages: /catalog (public courses), /catalog/[id] (course details), /learning (enrollments)
- Add LessonQuiz component with scoring and results
- Update sidebar navigation: add Catalog and My Learning links
- Add publish/verify buttons in course editor
- Integrate enrollment progress tracking with backend

All courses now support: sequential progression, quiz tests, reviews, ratings,
author verification badges, and full marketplace publishing workflow.

Co-authored-by: Cursor <cursoragent@cursor.com>

apps/web/src/lib/api.ts

@@ -179,6 +179,10 @@ class ApiClient {
     });
   }
 
+  async getLessonQuiz(courseId: string, lessonId: string) {
+    return this.request<any>(`/courses/${courseId}/lessons/${lessonId}/quiz`);
+  }
+
   // Generation
   async startGeneration(prompt: string) {
     return this.request<{ id: string; status: string; progress: number }>('/generation/start', {
@@ -231,6 +235,65 @@ class ApiClient {
     });
   }
 
+  // Catalog (public courses)
+  async getCatalog(params?: { page?: number; limit?: number; search?: string; difficulty?: string }) {
+    const searchParams = new URLSearchParams();
+    if (params?.page) searchParams.set('page', String(params.page));
+    if (params?.limit) searchParams.set('limit', String(params.limit));
+    if (params?.search) searchParams.set('search', params.search);
+    if (params?.difficulty) searchParams.set('difficulty', params.difficulty);
+    const query = searchParams.toString();
+    return this.request<{ data: any[]; meta: any }>(`/catalog${query ? `?${query}` : ''}`);
+  }
+
+  async getPublicCourse(id: string) {
+    return this.request<any>(`/catalog/${id}`);
+  }
+
+  async publishCourse(id: string) {
+    return this.request<any>(`/catalog/${id}/submit`, { method: 'POST' });
+  }
+
+  async toggleCourseVerification(id: string) {
+    return this.request<any>(`/catalog/${id}/verify`, { method: 'PATCH' });
+  }
+
+  // Enrollment & Progress
+  async enrollInCourse(courseId: string) {
+    return this.request<any>(`/enrollment/${courseId}/enroll`, { method: 'POST' });
+  }
+
+  async getMyEnrollments() {
+    return this.request<any[]>('/enrollment');
+  }
+
+  async getEnrollmentProgress(courseId: string) {
+    return this.request<any>(`/enrollment/${courseId}/progress`);
+  }
+
+  async completeLesson(courseId: string, lessonId: string) {
+    return this.request<any>(`/enrollment/${courseId}/lessons/${lessonId}/complete`, { method: 'POST' });
+  }
+
+  async submitQuizScore(courseId: string, lessonId: string, score: number) {
+    return this.request<any>(`/enrollment/${courseId}/lessons/${lessonId}/quiz`, {
+      method: 'POST',
+      body: JSON.stringify({ score }),
+    });
+  }
+
+  async createReview(courseId: string, data: { rating: number; title?: string; content?: string }) {
+    return this.request<any>(`/enrollment/${courseId}/review`, {
+      method: 'POST',
+      body: JSON.stringify(data),
+    });
+  }
+
+  async getCourseReviews(courseId: string, page?: number) {
+    const params = page ? `?page=${page}` : '';
+    return this.request<{ data: any[]; meta: any }>(`/enrollment/${courseId}/reviews${params}`);
+  }
+
   // Search
   async searchCourses(query: string, filters?: { category?: string; difficulty?: string }) {
     const searchParams = new URLSearchParams({ q: query });