Cannes: Oscar-winning writer/director Arthur Harari ("Anatomy of a Fall") introduces us to his mind-bending film, starring Niels Schneider as a man who wakes up in Seydoux's body after a bizarre sexual encounter. Arthur Harari knows his case is strange.  At 45, the filmmaker behind “ The Unknown ” hits Cannes competition with an Oscar, two Césars , and an international profile that still feels undefined and oddly elusive. He prefers it that way.  “Obviously, like everyone in this profession, I