One part model — a revolved or prismatic profile plus typed features — and one
view engine that projects it into front/side/section/detail views with hidden
lines, cut faces and dimensions, instead of a generator per part shape. Around
it: the standard-parts catalogue as code inserted as blocks with attributes,
the ISO annotation symbols, and the sheet standard (ISO 5457 frames A4-A0,
ISO 7200 title blocks, revisions, ISO 7573 parts list, balloons, xrefs, DWG).
25 tools in four sections, new pack `mech`, three capability keys, six mech_*
critique focuses, benchmark task `mech_assembly` and six correctness checks.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01FKFStjEFzpGyLq5bMpWxTd
