{"message":"Welcome to Quiz Exam API","endpoints":{"register":"/register","verify_otp":"/verify-otp (also used for guest login after OTP)","resend_otp":"/resend-otp","login":"/token","logout":"/logout (POST)","me":"/me (current user info)","user_name":"/user/name (first_name, last_name for current user – guest or regular)","forgot_username":"/forgot-username (email → OTP; then POST /forgot-username/verify to get username)","forgot_password":"/forgot-password","quizzes":"/quizzes","take_quiz":"/quiz/{quiz_id}","can_take_quiz":"/quiz/{quiz_id}/can-take","submit_quiz":"/quiz/submit","my_attempts":"/my-attempts","certificate_html":"/certificate/html","certificate_pdf":"/certificate/pdf","certificate_email":"/certificate/email (POST – send certificate to user email)"}}