Action matrix: every ordinary action on every face, edge, vertex and body of the design corpus (#553)

apps/solidcraft-cli/tests/action_matrix.rs tries sketch, offset/angle/mid planes, press pull, extrude from a face, hole, draft, shell, fillet, chamfer, axes, points, planes, projection, move, copy, mirror and pattern on the final bodies of 104 designs (the old design files, the examples, the 76 reference recipes, the enclosure demos, the Pi case built through the UI, eight typical parts), through the commands and picks the desktop sends, each design in its own process, with an edit round on a sample of passes. tests/action_matrix/baseline.json is a ratchet: an action that passed there and fails now fails the test; newly passing ones are reported for cargo xtask action-matrix --bless. Every CI run checks a fixed sample; the nightly Action matrix job runs the whole matrix in four parts. 30,567 of 35,576 actions pass (85.9%); results and causes in docs/action-matrix.md, one ignored reproduction per open cause (#556-#568).

Co-Authored-By: Claude Opus 5.5 <[email protected]>

CONTRIBUTING.md

@@ -166,6 +166,11 @@ Pull requests skip a few heavy tests (one to four minutes each), which run on ev
 - `solidcraft-kernel`: `tests::boolean_identity_on_tangent_primitives`
 - `solidcraft-ui-egui` scenarios: `acceptance_sensor_enclosure`
 
+**The action matrix** tries every ordinary action on every face, edge, vertex and body of a
+corpus of designs against a checked-in ratchet ([docs/action-matrix.md](docs/action-matrix.md)).
+A pull request that makes an action pass should record it with `cargo xtask action-matrix --bless`;
+one that makes a passing action fail fails the sample every CI run checks.
+
 **The reference tests** are 76 parts in [`tests/oracle/`](tests/oracle/), each a `recipe.json`
 in our own format with an `expected.json` beside it. SolidCraft rebuilds the recipe and compares
 body count, volume, area, centre of mass and bounding box (and, where there is a `reference.stl`,