While Casey Affleck, Ben Foster and “Girls” star Alex Karpovsky milled around a VIP bar at BAMcinemaFest’s opening night, the real star of the after-party at Skylight One Hanson was a long table in the former bank lobby lined with endless jars of candy. Guests gobbled gummy bears and other goodies while discussing the less sweet news Wednesday night thatJames Gandolfini just died. The crowd had been cocooned in a Cinema Society screening of Affleck’s “Ain’t Them Bodies Saints” when the news first broke. Anna Chlumsky, who co-starred with “The Sopranos” star in “In the Loop,” reminisced the about beloved actor with a gaggle of IFC execs. Also at the screening: Kelly Bensimon.