By Brian Straus The format for the full-sized Leagues Cup, which kicks off in the summer of 2023, has been revealed. The enlarged, official Leagues Cup tournament, which will comprise all 47 clubs in MLS and Liga MX and send the top three finishers to the Concacaf Champions League, will kick off July 21 with a 45-team group stage. The month-long competition will require an unprecedented pause in both MLS and Liga MX schedules and will conclude with the third-place game and final on Saturday, Aug. 19. Each of the 77 Leagues Cup matches will be played in the U.S. or Canada. MLS unveiled some det…