Beyond the nails, one-legged tracksuits, and world records, Florence Griffith Joyner set the stage for women to build million-dollar brands — Nearly 32 years ago, Florence Griffith Joyner solidified herself as an international sensation. The sprinter, more commonly known as Flo Jo, raced into the spotlight with record-setting speed, winning four medals — three of them gold at the 1988 Olympics in Seoul. Though she had a decorated track career since…