In colored mode (textures on), every item now renders its authored material
— textures, vertex colours, and default colours — instead of being stripped
to the uniform off-white baseMaterial. AI-generated and vertex-coloured items
show their real appearance; slot resolution (override -> curated -> authored)
is unchanged. Monochrome (textures off) still collapses to the furnishing
clay role colour (the escape hatch). Drops the now-unused isAuthored marker.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
