LOS ANGELES, March 24 (Reuters) – When Cassidy Jacobson was 13 years old, she posted a video of herself dancing on the popular app TikTok. Little did she know then that six years later her Casssidy_J account would have 1.5 million followers on the short-form video platform with fans drawn to her love of dance and hair care. Jacobson dreams of using her success on TikTok – an app used by 150 million Americans – to start her own curly hair care line and inspire others to love their natural curls. That dream and those of other TikTok creators may…