It’s not easy to adopt a Zen approach to life in New York City. The handful of locals who gather regularly at a Buddhist center in Emma Sheanshang’s new play, “The Fears,” don’t have to tell you this; in the world premiere production, the first thing we hear is the roar of traffic. Moments later, the drilling starts, and during the 90-minute play we also hear sirens wailing, to say nothing of the profanity-pocked exchanges that unfold on the street.