voxolithregisterTreeGenerators()
Register both generators with the engine registry.
generateTree()
Generate a tree: grow the skeleton, voxelise and bark the wood, hang and carve the foliage, shade it, apply the season, then drop anything not connected to the base, so the result is always one piece. Pure and deterministic: the same params and rng sequence give the same tree.
skinFor()
Default role colours for a species in a season: bark, twigs, and that season's leaves, blossom and snow. Unknown species fall back to oak.