A grateful and at times defiant Donald Trump told The Post Sunday he’s “supposed to be dead” as he recalled the harrowing moment a would-be assassin shot him at a Pennsylvania campaign rally. The former president shared the “very surreal experience” that nearly ended his life during an interview aboard his private plane enroute to Milwaukee for the GOP National Convention. “The doctor at the hospital said he never saw anything like this, he called it a miracle,” said Trump, who was sporting a loose, large white bandage that covered his right ear. His staff insisted that no photos be...