Julien Segura was fresh off volunteering for the campaign of insurgent New York City mayoral candidate Zohran Mamdani, when he launched his own run for State Assembly. After Tuesday night, when the results of the state primaries begin to come in, the 29-year-old progressive will find out if he will join the ranks of local New York politicians. For the last five years, Segura, a lifelong resident of Sugar Hill in Harlem, a predominantly Latino-Ca…