Two root causes found for ca/cb corpus parity failures:
1. _avg_path_len_from used unweighted BFS (hop count) but Perl's
Graph::average_path_length uses weighted Dijkstra with centroid-to-centroid
edge distances. This caused wrong edge removal in has_circulation, giving
wrong stack corner counts (2 instead of 3 for lr in ca9e80c5).
2. Entrance corner logic used _public_access (any street boundary) but Perl's
Entrances() picks the best entrance route — a stair only gets entrance corners
if no higher-priority non-stair C leaf has public access.
Also includes homemaker-py-hgg storey/building checks previously uncommitted:
stair fit, circ connectivity, roof-garden, public-access tracking, has_circulation,
corners_in_use, stack_corners_in_use, check_space_counts with failure stacking.
All 4 debug corpus prefixes: ratio=1.000000. 39 tests pass.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Clean-room Python successor to Urb for programme-driven layout search.
This initial commit establishes the .dom bridge format and a faithful
port of Urb's top-down quad geometry, validated byte-identical against
Urb across all 35 programme-house example files (including the wall
inset and multi-storey wall-stacking inheritance).
- dom.py: .dom YAML <-> Node tree, parent/below/position linkage,
wall_outer inset on load, raw-corner stash for round-tripping
- geometry.py: Coordinate/Coordinate_a/_b/Area/Length + Coordinate_Offset
- experiments/dump_areas.{py,pl}: geometry regression harness
