- Add 'concrete-drywall' (Prepared Drywall) catalog finish + 512 KTX2/webp
runtime assets; default walls (WALL_SLOT_DEFAULT interior+exterior) and the
roof wall/trim band to it so roofs read continuous with walls.
- fence: replace the 2-slot panel/rail split with 4 slots that match the panel's
build options — posts / infill (showInfill) / base (grounded only) / rail —
each its own mesh with userData.slotId; conditional slots track the build
state. Defaults: posts/infill/base charcoal, rail wood-finewood27.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>