With an ear-piercing whistle, a professional clown in the crowd startles to order a conference room full of some of the world’s elite thinkers, writers and religious minds. The Lebanese-born, curly-haired artist in baggy green trousers and with a frequent raspy laugh made her debut this week at the World Economic Forum in Davos, Switzerland, a special invitee more accustomed to entertaining refugees than livening up serious thought-fests.