AUSTIN, Texas — Five months before the World Cup, the U.S. men’s soccer team has a striking problem. A pile of players has tried to claim the mantle of being the Americans’ leading forward, but none has done so. For a while, Josh Sargent was “the guy,” but then he had a bad season with England’s Norwich City. Ricardo Pepi was even more “the guy” after a blazing start to World Cup qualifying, but then he lost all his momentum after a $20 million move to Germany’s Augsburg. Jordan Pefok scored 27 goals in 45 games this season, and might be the best pure finisher on the board. But he’s injured ri…