The siege of Gaza played out before a packed house at Oakland’s Regal Jack London theater, where the documentary “Bisan,” created by Palestinian journalist and filmmaker Bisan Owda about her daily life, had a rare screening Wednesday. Some in the audience cried softly as they bore witness to the horrors of Israel’s 2023-24 siege of Gaza: buildings falling, bombs exploding, children screaming. The documentary was compiled entirely from social media clips shot by Owda. Her posts have found a large…