Plagued by injuries, obstinance and absenteeism, the New York Mets have managed to win seven of 10 following a six-game losing streak. ''Considering all that's going on around here, we're doing a really good job of compartmentalizing and focusing on what's going on on the field,'' Neil Walker said after his two-out single in the ninth inning lifted the Mets over the San Francisco Giants 4-3 Monday night. Down 2-0 and 3-2 against the team it lost to in last year's NL wild-card game, the Mets rallied to put aside their constant controversy.