House of Soul owner Nichol Stevenson has never been interested in the spotlight. After more than two decades in the entertainment industry as a manager, event producer — and now a club owner — she still moves like someone who prefers to work behind the scenes rather than stand at center stage. “I just love us,” Harrell said. “I truly do.” Most of the thousands who filled Washington Avenue between 12th and 14th streets wouldn’t recognize her in a…