Add lesson content editor, quiz test endpoint, and lesson update API

- Backend: UpdateLesson handler (PUT /lessons/:id) for editing title, content, quiz questions
- Backend: TestQuiz handler (POST /lessons/:id/quiz-test) for quiz evaluation without enrollment
- Frontend: Content editor with markdown textarea, save, and approve-for-video workflow
- Frontend: Fix quiz endpoint to /lessons/:id/quiz-test

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

ai-compliance-sdk/internal/academy/store.go

@@ -331,6 +331,23 @@ func (s *Store) GetLesson(ctx context.Context, id uuid.UUID) (*Lesson, error) {
 	return &lesson, nil
 }
 
+// UpdateLesson updates a lesson's content, title, and quiz questions
+func (s *Store) UpdateLesson(ctx context.Context, lesson *Lesson) error {
+	quizQuestions, _ := json.Marshal(lesson.QuizQuestions)
+
+	_, err := s.pool.Exec(ctx, `
+		UPDATE academy_lessons SET
+			title = $2, description = $3, content_url = $4,
+			duration_minutes = $5, quiz_questions = $6
+		WHERE id = $1
+	`,
+		lesson.ID, lesson.Title, lesson.Description,
+		lesson.ContentURL, lesson.DurationMinutes, quizQuestions,
+	)
+
+	return err
+}
+
 // ============================================================================
 // Enrollment Operations
 // ============================================================================