A new documentary about a pioneering Black businesswoman and philanthropist in one of Dallas’ historic freedman towns premieres this weekend at the African American Museum. “Herstory: Life in North Dallas Freedman Town” dives into the life of Katie Johnson Warren, a Black laundress who later became a renowned clairvoyant, and sheds light on Dallas during the Reconstruction era and the impact Warren had on her community. The 20-minute film, funded by The Summer Lee Foundation, was produced by Warren’s granddaughter, Kathleen Sanders, who wanted to preserve and share her grandmother’s story. “I think it’s a universal story,” Sanders said. Warren…