feat(ground): add reviewed static-plane skid/roll reference (#4271)

[d-sorgcodexagent]

Scope

Publishes the reviewed, UI-independent Python reference continuation for issue #4271 on exact corrected #4270 parent 920c46dee688815691e251777142126bf1489b1a.

This is a bounded first slice, not issue closure: it qualifies one immutable arbitrary-orientation plane with an optional finite tangent-axis edge. Changing normals, material regions, terrain deformation, UI, compiled runtimes, and downstream parity remain explicitly open.

Delivered

• kinetic Coulomb skid, static-feasibility gate, pure roll, rolling resistance, retained axial spin, qualified rest, and exact finite-edge termination;
• adaptive oblique-slip integration preventing zero-manifold overshoot and step-size resonance while preserving exact collinear capture;
• passive translation/rotation/gravity/moving-surface work ledger and distinct skid/roll paths;
• canonical request SHA-256 binding across impact, bounce, skid/roll, and composition phases;
• strict terminal state/trajectory/event/termination consistency and fail-closed unrepresentable outcomes;
• composed two-phase model identity, enduring impact material limitations, and removal of fulfilled stage-only notices;
• exact prefix/suffix composition without duplicate or fabricated epsilon timestamps;
• scientific specification, campaign manifest, SPEC update, and all three canonical handoffs.

Independent review corrections

The initial local implementation was withheld after review found six blockers. The reviewed implementation lineage includes regressions and fixes for oblique-slope convergence, zero-speed downhill starts, immediate outward edge departure, cross-request prefix reuse, contradictory final-state evidence, and stale #4302 carrier metadata. The reviewer re-ran the adversarial sweep and confirmed every blocker closed before publication.

Hosted quality-gate run 31354071845 then exposed ten deterministic MyPy 1.13 no-any-return findings because the changed-file CI lane uses --follow-imports=skip. Immutable corrected implementation f475ae85feea1b2c628f756699b2aba6ea9334fb explicitly normalizes the already validated NumPy-backed scalar boundaries to float/bool; physics, values, integration ordering, schema, output, API, scope, and base are unchanged.

Verification

• 115/115 full ground tests on CPython 3.11.9;
• 115/115 on isolated real CPython 3.10.20 (five expected missing-plugin configuration warnings only);
• exact hosted-style and full-package pinned MyPy 1.13 clean across all 25 ground production modules;
• pinned Ruff 0.14.10 check/format clean for the corrected production files and previously clean full package;
• campaign manifest validator plus 8/8 manifest contract tests;
• documentation governance, changed-test assertion, structural, file-size, and diff gates.

Exact stack state

• Base branch: feat/4270-ground-impact-bounce
• Exact parent: 920c46dee688815691e251777142126bf1489b1a
• Immutable corrected implementation evidence: f475ae85feea1b2c628f756699b2aba6ea9334fb
• Current documentation/evidence carrier: 482cdf272b04c78b50da91a6d2ddd4d15e063c7b
• No retarget, rebase, force-push, parent rewrite, admin merge, or protected-check bypass was used.

Issue #4271 remains open until regional/changing-normal surfaces and its remaining acceptance criteria are implemented and protected release evidence exists. Fresh protected CI and review remain required; the failed hosted run was not manually retried.

[dieterolson]

Consolidated into #4409. Closing to eliminate CI runner load.