docs: updated docs heading structure

[nikkimk]

Description

• Updating contributor docs to include "States" section heading.
• Updating readme template to include recommended heading structure.

Related issue(s)

• SWC-91

Motivation and context

Documentation should provide more information and examples that demonstrate how to use the components accessibly.

How has this been tested?

Review the recommended documentation structure

• Create a new component locally via yarn new-package. Does the new component's readme match the recommended heading structure?

Screenshots (if appropriate)

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Chore (minor updates related to the tooling or maintenance of the repository, does not impact compiled assets)

Checklist

• I have signed the Adobe Open Source CLA.
• My code follows the code style of this project.
• If my change required a change to the documentation, I have updated the documentation in this pull request.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.
• I have reviewed at the Accessibility Practices for this feature, see: Aria Practices

Best practices

This repository uses conventional commit syntax for each commit message; note that the GitHub UI does not use this by default so be cautious when accepting suggested changes. Avoid the "Update branch" button on the pull request and opt instead for rebasing your branch against main.

[changeset-bot]

⚠️ No Changeset found

Latest commit: 4febb9c

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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[nikkimk]

This section was needed as we started documenting components with states like disabled and pending, so it has been added for consistency.

[nikkimk]

Updated the new component readme template to match the recommended heading structure.

[github-actions]

Branch preview

• Documentation Site
• Storybook

Review the following VRT differences

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

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.

[github-actions]

Tachometer results

Currently, no packages are changed by this PR...

[castastrophe]

This looks excellent! Thanks so much for tackling this.