By Tom Verducci The two superstars have been on parallel tracks for years. Now, they face off with a World Series appearance on the line SAN DIEGO — At age 17, Bryce Harper and Manny Machado shared a bunk bed at a dorm in Barquisimeto, Venezuela. Teammates then on the USA 18U national team, this week they are opponents fighting for same prize: a spot in the World Series. In the 13 years in between, Harper and Machado have moved in near lockstep building prolific, Cooperstown-tracking careers. Each was drafted in 2010 with one of the first three picks. Each reached the big leagues at such a you…