Pool slabs (generatePoolGeometry) were the one procedural surface emitting
normalized [0..1] floor UVs, so a textured finish stretched to fit the pool
instead of tiling at real-world scale like every other surface. Switch the
floor to shape-space metres (x, -z) — the same mapping generatePositiveSlab-
Geometry already uses for its caps. Pool walls were already in metres.
Also document the contract in wiki/architecture/materials-and-themes.md: every
procedural surface generates UVs in metres (1 UV unit = 1 m), GLB slots follow
the same ~1 unit/m authoring convention, and a catalog material's `repeat` is
therefore a per-material world-scale setting (tiles per metre), identical for
every surface that uses it — never per-item.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
