@hatch:spatial v0.2.1

Spatial acceleration structures for 2D and 3D worlds. ClusterGrid for uniform-density buckets, Octree for adaptive 3D partitioning, Quadtree2D for sprite / UI hit-testing, and BVH over AABBs for ray casts and frustum culling. Pure Wren; composes with @hatch:gpu's Camera3D + Frustum for cull and LOD pipelines and with @hatch:noise for procedural density sampling.