Every Unity.Mathematics using, alias and qualified name under Assets\Scripts
and tools now names CultMath. The nine `using static ...noise;` lines are
gone: snoise lives on CultMath's math. UnityExtensions loses float4.ToColor
and Color.ToFloat4, which duplicate the bridge's ToColor and ToCultMath; the
float3 colour pair stays because the bridge has none.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
