T he new Superman, David Corenswet, resides not in Metropolis but a suburb of Philadelphia. He’s close enough to the downtown train station that his commute to Manhattan, he claims, feels shorter than when he lived in Brooklyn as a struggling actor. We meet at the kind of diner with syrup and hot sauce on every table, on a quaint main street that ends, inevitably, at a Wawa convenience store. It’s an unusual home base for an actor on the precipice of a major breakthrough. Corenswet, 31, will