docs(action-button): a11y migration analysis

[nikkimk]

Description

In spectrum-web-components/CONTRIBUTOR-DOCS/03_project-planning/03_components/action-button/accessibility-migration-analysis.md:

• Documented recommendations for ARIA roles, states, and properties for the 2nd-gen action button
• Shadow DOM and cross-root ARIA considerations documented, including any limitations or required workarounds (e.g., ElementInternals, cross-root ARIA delegation)
• Accessibility tree expectations documented, including expected node roles, names, states, and hierarchy
• Keyboard interaction model fully specified, covering focus management, key bindings, roving tabindex or active-descendant patterns, and focus trapping where applicable
• Testing requirements defined, including unit tests, integration tests, and manual screen reader testing matrix (JAWS, NVDA, VoiceOver)
• Known 1st-gen accessibility issues cataloged with disposition (fix in 2nd-gen, defer, or won't fix) and linked to any open GitHub issues or bugs
• Applicable WAI-ARIA design pattern identified with relevant ARIA roles documented
• 1st-gen component analysis completed, covering current ARIA implementation, keyboard handling, existing test coverage, and known issues with dispositions

Motivation and context

The 2nd-gen migration is an opportunity to address known accessibility gaps, align with the latest WAI-ARIA Authoring Practices, and ensure the component meets WCAG 2.2 AA compliance.

Related issue(s)

• resolves SWC-2040

Screenshots (if appropriate)

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Author's checklist

• I have read the CONTRIBUTING and PULL_REQUESTS documents.
• I have reviewed at the Accessibility Practices for this feature, see: Aria Practices
• I have added automated tests to cover my changes.
• I have included a well-written changeset if my change needs to be published.
• I have included updated documentation if my change required it.

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Reviewer's checklist

• Includes a Github Issue with appropriate flag or Jira ticket number without a link
• Includes thoughtfully written changeset if changes suggested include patch, minor, or major features
• Automated tests cover all use cases and follow best practices for writing
• Validated on all supported browsers
• All VRTs are approved before the author can update Golden Hash

Manual review test cases

Review the Action button accessibility migration analysis

• ARIA roles, states, and properties covered
• Shadow DOM and cross-root ARIA considerations covered
• Accessibility tree documented
• Keyboard interaction fully specified
• Testing requirements defined
• Known 1st-gen issues cataloged with dispositions

[changeset-bot]

⚠️ No Changeset found

Latest commit: 3da37f1

Merging this PR will not cause a version bump for any packages. If these changes should not result in a new version, you're good to go. If these changes should result in a version bump, you need to add a changeset.

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[github-actions]

📚 Branch Preview Links

• Documentation Site (first-gen)
• Storybook (first-gen)
• Storybook (second-gen)

🔍 First Generation Visual Regression Test Results

When a visual regression test fails (or has previously failed while working on this branch), its results can be found in the following URLs:

• Spectrum | Light | Medium | LTR
• Spectrum | Dark | Large | RTL
• Express | Light | Medium | LTR
• Express | Dark | Large | RTL
• Spectrum-two | Light | Medium | LTR
• Spectrum-two | Dark | Large | RTL
• High Contrast Mode | Medium | LTR

Deployed to Azure Blob Storage: pr-6276

If the changes are expected, update the current_golden_images_cache hash in the circleci config to accept the new images. Instructions are included in that file.
If the changes are unexpected, you can investigate the cause of the differences and update the code accordingly.

[cdransf]

This looks great! ✨