NEW YORK — For decades, Wayne LaPierre, the National Rifle Association’s longtime leader, has been a survivor. He has endured waves of palace intrigue, corruption scandals and embarrassing revelations, including leaked video that captured his inability to shoot an elephant at point-blank range while on a safari. But now, LaPierre, 74, faces his gravest challenge, as a legal showdown with New York Attorney General Letitia James goes to trial in a Manhattan courtroom. James, in a lawsuit filed ami