Piper Curda remembers exactly where she was when she found out she’d booked the lead role in “ Hoppers ,” Pixar’s latest animated feature.  Curda was lounging in her Chicago apartment with her best friend when her agent called with “the most insane opportunity of my life.” She and her friend ordered Milk Bar for a mini celebration to mark the occasion. “The relative smallness of that moment is the perfect juxtaposition against how big the rest of this has been,” says Curda.  Mark Ruffalo Fires