NEW YORK — Bo Bichette’s fist pump revealed the magnitude of the moment. For Bichette, certainly. For the New York Mets, maybe.Full windup with his right arm. Complete motion across his chest. Nothing subtle about it. An unusual sight for someone who generally reserves outward emotion only for special moments. Upon passing first base on his fast trot after hitting a grand slam, his second of two home runs on Friday night, Bichette looked like someone who had just unburdened himself.At last, after an abysmal slump to start his New York career, Bichette is starting to look like the star player the Mets have desperately needed him to be. After some false starts, New York’s 7-5 win over the first-place Atlanta Braves at Citi Field removed any doubt over whether Bichette’s hot stretch is for real. Finally, he created the Mets moment that he has openly craved.“I mean, it was a good feeling, for sure,” Bichette said in a subdued tone, “but I just want to keep on winning.”Could believing in Bichette mean believing in the Mets? No player epitomizes the Mets’ season quite like Bichette. His career .790 OPS and .289 batting average suggest he should be so much better than his season’s .635 OPS and .232 batting average. With their $368 million payroll, per FanGraphs, the Mets should be so much better than 31-38.Instead, the Mets are among Major League Baseball’s most disappointing teams.There is time for a turnaround, however. The Mets are 4 1/2 games behind the third and final wild-card spot. The group ahead of them features a batch of flawed teams, not super squads.Better health could help the Mets plenty. Francisco Lindor’s expected return at some point this month would be a significant step in that regard.The Mets’ issues, however, go beyond their injured players. All season, an inconsistent lineup has topped the list of problems.Perhaps things are starting to change there, too. Francisco Alvarez’s return lengthens the lineup. Rookies Carson Benge and A.J. Ewing are adding an energetic speed-and-contact dynamic. Jared Young offers a surprising amount of power. Juan Soto is still Juan Soto. Any belief from here, though, starts with Bichette.