Hitters aren’t supposed to get better at age 31, certainly not catchers, and certainly not catchers coming off Tommy John surgery. Salvador Perez doesn’t care. The seven-time All-Star is having a career month in what has been a career season. His 12 August home runs tied a club record for most home runs in a single month, and he tied Mike Sweeney’s record with home runs in five consecutive games. He has already set the record for most home runs by any American League player who has spent at least 75 percent of his games at catcher with a month left to go in the season.