A Milton man was arraigned in Boston Municipal Court Monday on charges of stabbing two people in the Theatre District, Suffolk District Attorney Daniel F. Conley’s office said. Njisane Chambers, 26, faces two counts of assault and battery with a dangerous weapon. Police outside the Rumor and Venu nightclubs saw a woman lying on the ground at about 2 a.m. Saturday as Chambers fought with a man nearby, Conley’s office said. A third man told police that Chambers stabbed him and the woman. A folding knife was found open on the ground, and both victims were taken to hospitals with injuries that were not considered life-threatening, prosecutors said.