ĀML hardening: independent verification, release discipline, evidence corpus

[aruintelligence]

Purpose

Consolidate the next ĀML hardening wave around independent verification, immutable release identity, and disciplined real-screen evidence.

Changes

• Moves verifier challenge cases into conformance/verifier-challenge-cases.json, a language-neutral corpus using a narrow RFC 6901 JSON Pointer replacement profile.
• Updates the black-box harness to consume that corpus while preserving the newer exact challenge/witness-vector SHA-256 bindings.
• Adds the case corpus and its SHA-256 to the reference-code-free External Verifier Kit without removing Snapshot 2/catalog/migration protections already on main.
• Updates regression tests so archived conformance evidence still verifies against the exact challenge contract while case definitions remain readable without inspecting canonical harness source.
• Adds docs/RELEASE_DISCIPLINE.md to separate stable, preview, and experimental states and define minimum release evidence.
• Adds docs/REAL_SCREEN_EVIDENCE_CONTRACT.md to standardize capture provenance, labels, policy binding, receipts, reruns, before/after evidence, and claim boundaries.
• Adds publications/INDEPENDENT_IMPLEMENTATION_CHALLENGE.md to invite outside clean-room implementations with PASS / FAIL / MIXED reporting.

Evidence boundary

A project-authored test or GitHub Actions result remains project-controlled evidence. A black-box PASS is compatibility evidence for the exact tested contract, not certification, proof of implementation independence, standards approval, scientific validation, regulatory compliance, safety, or adoption.

The attention/restoration labels used in real-screen experiments remain declared reviewer inputs, not objective measurements of cognition or wellbeing.

Relationship to older PRs

This PR modernizes the useful language-neutral verifier-case idea from #68 against current main rather than merging that stale branch wholesale. The real-screen evidence from #152 is already present in current main; this PR adds a forward evidence contract rather than overwriting those historical packages.

[aruintelligence]

Superseded by #166. main advanced substantially while this branch was under test, so the hardening changes were replayed as one clean commit on top of the newer main instead of forcing a stale merge. No evidence or intended functionality from this branch is being treated as independently validated merely because it was replayed.