Amid the humid mist and roaring waterfalls inside Brookfield Zoo’s Tropic World habitat, a new, tiny resident clung tightly to its mother and made an exclusive Sun-Times debut. A newborn squirrel monkey born July 30 to mother Gizmo and father Sandy. While the infant does not have a name yet and its sex remains unidentified, it is already thriving, spending its first days riding securely on its mother’s chest and back as she navigates the habitat…