InlineCadViewer: STL-derived GLBs have non-indexed geometry (unique vertex
per triangle face). computeVertexNormals() on non-indexed geometry produces
per-face normals (faceted shading). Fix: mergeVertices() first to create
shared/indexed geometry, then computeVertexNormals() averages across
adjacent faces → smooth shading. Indexed Blender GLBs are unaffected.
generate_gltf_geometry_task: asyncio.run() inside a Celery worker that
already runs asyncpg causes 'Future attached to a different loop'. Replace
async _store() with sync SQLAlchemy session (matching the rest of the task).
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Hartmut
2377cb192a