UI library for s&box that implements a virtual DOM style system called Goo, with a reconciler, applier, and a set of blob structs for panels, text, images, shapes, SVG, web, and scene panels. It includes animation utilities (tweens, timelines, springs, smooth/decay types), input helpers, drag and drop, shader effects with uniform management, and many generated style facades that map to Sandbox.UI StyleList. A GooPanel/GooView hosts the tree, diffs Frames to Fibers each frame, and applies Ops to actual Panels.