feat(paint-slots): round-2 feedback — fence 2 slots + UVs, roof defaults, stair body

- fence: split into two paint slots — panel (posts/base/infill, default charcoal)
  and rail (cap, default wood-finewood27) — as separate meshes with userData.slotId.
  Fix applyFenceUVs to continuous world-space 1 UV unit = 1 m (drop the per-part
  min origin that broke tiling across parts). New generateFenceSlotGeometries.
- roof: real catalog defaults for the segment surfaces via getRoofMaterialArray
  (the actual default path): wall/trim concrete-plate (matches walls), deck +
  soffit soft-white, shingle terracotta; textures-off role escape hatch kept.
  Align nodes getRoofMaterials no-parent fallback to match.
- stair: body slot default -> preset-lightgrey.
- (biome formatting normalization of the round-1 merged renderer files rides along.)

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

packages/nodes/src/column/renderer.tsx

@@ -2288,11 +2288,7 @@ function ColumnBody({ node }: { node: ColumnNode }) {
       <ColumnSlot slotId="shaft">
         <Shaft height={shaftLayout.shaftHeight} node={node} y={shaftLayout.shaftY} />
         <Rings node={node} shaftHeight={shaftLayout.shaftHeight} shaftY={shaftLayout.shaftY} />
-        <LatheBands
-          node={node}
-          shaftHeight={shaftLayout.shaftHeight}
-          shaftY={shaftLayout.shaftY}
-        />
+        <LatheBands node={node} shaftHeight={shaftLayout.shaftHeight} shaftY={shaftLayout.shaftY} />
         <Flutes node={node} shaftHeight={shaftLayout.shaftHeight} shaftY={shaftLayout.shaftY} />
         <LowerCarvedBand
           node={node}
@@ -2304,11 +2300,7 @@ function ColumnBody({ node }: { node: ColumnNode }) {
           shaftHeight={shaftLayout.shaftHeight}
           shaftY={shaftLayout.shaftY}
         />
-        <SpiralRibs
-          node={node}
-          shaftHeight={shaftLayout.shaftHeight}
-          shaftY={shaftLayout.shaftY}
-        />
+        <SpiralRibs node={node} shaftHeight={shaftLayout.shaftHeight} shaftY={shaftLayout.shaftY} />
       </ColumnSlot>
       <ColumnSlot slotId="capital">
         <Capital