It’s the first of its kind to offer work making public art, rather than picking up trash, pulling weeds, or other manual labor. It’s the first to enlist peer specialists, individuals who themselves have serious mental illnesses or histories of substance abuse and are trained to support others. And, unlike many other day-work programs around the country — some of which launched in cities like Lexington, Ky., and Portland, Maine, after outright bans on panhandling were overturned in court — organizers insist it is not intended to clear the streets but to offer an opportunity for those who choose to take it.