DXF generation and validation

Provenance: maintained in earthtojake/text-to-cad. Use the installed local skill files as the runtime source of truth; the repository link is only for provenance and release review.

Purpose

Create or modify 2D DXF drawings from natural-language requirements or from CAD geometry, generate validated drawing artifacts, and return checked outputs. A DXF drawing's source of truth is a dedicated Python generator file named <name>.dxf.py defining gen_dxf(); the CLI owns output paths.

The default build product is the drawing package — a render artifact the CAD Viewer serves and auto-regenerates:

<model-folder>/__cadgen__/models/<name>.dxf.py/
  drawing.json    # provenance + freshness descriptor
  drawing.dxf     # the built DXF (the exchange artifact)
  preview.glb     # the baked 3D flat pattern (what the viewer renders)