The 32-year-old Brooklyn man fatally stabbed by an unhinged suspect in a “horrific, brutal murder” Monday was remembered by friends as a big-hearted activist and talented poet — who once talked a mugger down from trying to rob him. Ryan Carson of Bedford-Stuyvesant was stabbed multiple times in the chest by a stranger just before 4 a.m. as he waited with his gal pal at the B38 bus stop at Lafayette Avenue and Malcolm X Boulevard – after the pair left a wedding, cops and sources said. “It’s a horrific, brutal murder of someone who worked piously to help make...