Summary

• replace opacity-only disabled styling on formulation builder navigation with explicit token-based disabled surfaces
• preserve native disabled semantics while keeping labels readable in light, dark, and forced-colors modes
• add Playwright coverage for disabled state, focus rejection, enabled transitions, and axe
• update Create label.yml #64 with the clean replacement disposition while leaving the unavailable historical worktree untouched

RAG impact: no retrieval behaviour change — UI-only disabled-state styling; no retrieval, ranking, answer, or source behavior changed.

Verification

• npm run verify:pr-local — passed on the clean current-main branch; includes build, client-bundle secret scan, 3,421 unit tests, and offline RAG fixture validation
• npm run verify:ui — equivalent product/test content passed all seven formulation journeys in PR Improve formulation builder disabled-state accessibility #1219; the prior local full run was 272/273 with only system Chrome’s unrelated PWA in-incognito result. This replacement requires clean hosted Production UI before merge.
• npm run verify:release — not run; provider-backed and not required for this UI-only change
• Focused formulation Chromium: 2/2 passed on this exact clean branch
• npm run verify:cheap: 3,421/3,421 passed

Risk and rollout

• Risk: Low — scoped Tailwind utility changes on two natively disabled buttons; no logic, API, data, auth, or clinical-output behavior changes.
• Rollback: Revert 70dd8cd9; no database or migration rollback is involved.
• Provider or production effects: None.

Clinical Governance Preflight

N/A — UI-only disabled-state presentation; no ingestion, answer generation, retrieval/ranking, source rendering, document access, privacy, production environment, or clinical output behavior changed.

Notes

• This branch is a clean replay directly on current main, created because PR Improve formulation builder disabled-state accessibility #1219 became GitHub-conflicted after automated branch synchronization. PR Improve formulation builder disabled-state accessibility #1219 must not merge.
• Two independent frontend/accessibility and regression reviews found no P0-P2 findings on the identical product/test change.
• The historical agent/formulation-disabled-contrast worktree remains preserved but unavailable. This PR does not modify or discard it.
• Merge only after all required hosted checks, especially Production UI, are green.