NEW YORK — Michael Musto can’t bring himself to ask his regulars at his Staten Island restaurant, Cargo Cafe, to prove they’ve been vaccinated against the coronavirus.So if New York City presses on with its plans to require eateries, bars, gyms and many other public gathering places to require patrons to show proof of vaccination before coming indoors, he will again shutter his dining room and move operations outside.“I just don’t see myself doing that, asking for proof,” Musto said. Barely half of his neighborhood’s …