Implement sculpt mesh and OBJ support (#43)

README.md

@@ -165,5 +165,12 @@ radius, and revolutions; cap and side winding; normals, UVs, viewer faces, and
 prim-face indexing. Geometry allocation and index arithmetic are bounded, and
 identical finite inputs produce deterministic mesh output on every supported
 platform.
+Sculpt maps are sampled through the same checked imaging abstraction and can
+produce plane, sphere, torus, and cylinder topology with reference seam,
+mirror, inversion, LOD, normal, UV, and viewer-face behavior. Native viewer
+indexing deduplicates vertices per prim face, while bounded Wavefront OBJ
+ingestion preserves object/group output and position/UV/normal associations.
+Malformed dimensions, channel layouts, topology, and indices return typed
+errors without partial meshes or panics.
 The controlled audit aggregates every expected failure by standardized C#
 member ID and rejects unrelated fixture, assertion, compile, or symbol errors.