fix(macos): stabilize Environment Brief accessibility layout

[jasoncavinder]

Summary

• What changed: Replaced the Environment Brief's duplicated responsive header branches with one stable custom-layout subtree, exposed the visible state title through native heading semantics, kept the Course Indicator as a separate noninteractive percentage element, localized readiness announcements in title-before-count order, and updated the v0.20 validation/state contracts.
• Why: Implement the accessibility correction tracked by Environment Brief heading is missing from VoiceOver rotor and FKA traversal is asymmetric #388 without reintroducing the rejected detached accessibility representation, while keeping the manual closure gate open until an attributable exact-source owner rerun is recorded.

Branch Policy

• Base branch is correct for this scope (dev or main hotfix/promotion flow).
• Head branch naming follows policy.
• If targeting main, source branch is valid per the categories above.

Scope Declaration

• App/core/runtime changes included
• Docs-only changes included
• Website-only changes included

Validation

• Relevant local validation was run (tests/lint/build as applicable).
• Required CI checks for the target branch are expected to pass.
• No unrelated changes were bundled.
• If docs were changed, terminology matches contract (manager/task/service for user-facing docs; adapter reserved for architecture/developer docs).

Automated evidence:

• Full arm64 UI quality gate: 338 tests, 0 failures.
• Focused responsive-layout and localization-order regressions passed.
• Locale integrity, length, and canonical/bundled mirror checks passed.
• Documentation sync, release-line validation, and diff checks passed.

The owner observed the expected heading-rotor, focus-geometry, separate-percentage, bidirectional Full Keyboard Access, readiness-announcement, and wide/vertical layout behavior in a 2026-08-25 pre-commit artifact. Independent review found that the evidence record retained binary hashes but not an exact source revision, tracked-clean tree, or source-blob equivalence mapping. Those observations are now consistently classified as bounded unattributed evidence and do not close #388.

This PR does not switch the production onboarding route, claim participant validation, or close the separate whole-workflow accessibility, Ventura, Sparkle-handoff, or moderated-research gates.

Release Impact

• No release impact.
• Release impact exists and checklist/docs were updated (docs/RELEASE_CHECKLIST.md, docs/CURRENT_STATE.md, docs/NEXT_STEPS.md).

SQLite Migration Safety

• This PR does not change SQLite migrations or migration behavior.
• If it does, the change only appends a new migration and manifest entry; frozen origin fixtures and preservation/rollback/reset tests were updated.
• If it does, scripts/ci/check_sqlite_migration_compatibility.sh passed and the migration safety changes received independent review.

Related to #388.

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View logs

[jasoncavinder]

Independent review found one blocking evidence issue.

• [P1] Issue Environment Brief heading is missing from VoiceOver rotor and FKA traversal is asymmetric #388 is closed using an unattributed pre-commit artifact. The readiness record says the 2026-08-25 owner artifact was built from source “later committed unchanged as 2c8726a0,” but it records only executable and dylib hashes. It does not retain an exact source revision, a tracked-clean tree, or a source-blob equivalence capture for that build. The same readiness document correctly classifies another pre-commit artifact without such a mapping as bounded unattributed evidence. As written, the closure claims in the readiness record and synchronized source-of-truth docs, the PR’s merge-readiness statement, and Closes #388 are therefore not supportable from the retained evidence.

The implementation, accessibility approach, localization changes, and automated coverage otherwise reviewed cleanly. I’ll remediate this by retaining those improvements while reclassifying the owner observations and reopening the bounded #388 gate until an attributable exact-source owner matrix is recorded.

[jasoncavinder]

Follow-up: the independent-review finding is remediated in 9db1a6fc.

• Reclassified the 2026-08-25 owner artifact consistently across all six affected source-of-truth documents as bounded unattributed pre-commit evidence.
• Reopened Issue Environment Brief heading is missing from VoiceOver rotor and FKA traversal is asymmetric #388's owner-validation gate and the combined Task 7 accessibility checklist item pending an attributable exact-source rotor, focus-geometry, bidirectional Full Keyboard Access, and wide/vertical rerun.
• Preserved the implementation and automated evidence: one stable responsive header subtree, native rendered-title heading semantics, a separately announced noninteractive percentage, title-before-count readiness announcements, and the 338-test arm64 UI gate.
• Narrowed the PR title/body, removed Closes #388, and verified GitHub reports no closing-issue reference; Environment Brief heading is missing from VoiceOver rotor and FKA traversal is asymmetric #388 remains open.

Final re-review is clean. Docs sync, release-line validation, Docs Checks equivalent, merge-marker checks, and diff hygiene pass. The remediation changes docs only; app/localization/test trees are unchanged from the reviewed implementation. The PR is ready to merge within this narrowed scope, while #388 should remain open for the attributable exact-source owner rerun.

[jasoncavinder]

Remediation is complete in 9db1a6fc.

• Reclassified the 2026-08-25 artifact consistently as bounded unattributed pre-commit evidence across all six source-of-truth documents.
• Reopened Issue Environment Brief heading is missing from VoiceOver rotor and FKA traversal is asymmetric #388 and the combined Task 7 accessibility item pending an attributable exact-source owner rerun.
• Narrowed the PR title/body, removed the auto-close directive, and retained the implementation plus automated evidence without overstating manual sign-off.

Verification passed: full arm64 UI quality gate (338 tests, 0 failures), focused accessibility/localization coverage, locale integrity and mirror parity, docs sync, release-line validation, merge-marker checks, and diff hygiene. Two independent re-review lanes found no remaining issue; GitHub reports no closing-issue reference and #388 remains open.

The PR is ready to merge for its narrowed implementation scope. The exact-source owner rotor/geometry/bidirectional-FKA/wide-and-vertical rerun remains a separate open gate under #388.