J Balvin and Ryan Castro have been awake since 5 a.m., but if they’re tired, there’s no way you would be able to tell. By mid-morning, the two Colombian stars are dressed in impeccably tailored suits on an unusually scorching April day in New York, dancing to reggaeton music blasting through a pair of speakers. As they gear up to talk about their joint album, Omerta , for the first time, they’ve made the occasion a full-blown, impromptu family gathering.  Their large crews have joined them,