docs: Add 2nd-gen TypeScript style guide and Storybook docs automation

[caseyisonit]

Description

Adds a comprehensive TypeScript style guide for 2nd-gen component development and automates publishing contributor docs to Storybook.

Motivation and context

Contributors (human and AI) need clear, consistent guidance for writing 2nd-gen components. This PR provides detailed conventions for file organization, class structure, decorators, types, and composition patterns—all based on the Badge component as the reference implementation.

Additionally, contributor docs are now automatically converted and displayed within Storybook, making them easier to discover and browse alongside component documentation.

Related issue(s)

• fixes [SWC-1420]

Screenshots (if appropriate)

N/A - documentation changes

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.

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

• Verify TypeScript guide renders correctly in Storybook

  1. Run yarn storybook in 2nd-gen/packages/swc
  2. Navigate to the Contributor Docs section
  3. Confirm the TypeScript style guide pages load and display properly

• Verify navigation structure is accurate

  1. Open CONTRIBUTOR-DOCS/02_style-guide/02_typescript/README.md
  2. Confirm all 15 linked guides exist and have correct content

Device review

• Did it pass in Desktop?
• Did it pass in (emulated) Mobile?
• Did it pass in (emulated) iPad?

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Summary of changes:

Area	Files	Description
TypeScript style guide	15 new docs	File organization, class structure, decorators, types, composition patterns
Storybook automation	generate-contributor-docs.mjs	Converts markdown docs to MDX for Storybook display
Minor fixes	Badge, sized mixin	Small updates aligned with documented patterns

[changeset-bot]

⚠️ No Changeset found

Latest commit: 9eb176f

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.

This PR includes no changesets

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[caseyisonit]

this correctly keeps 1st-types working but closer to 1st-gen. this is the pattern for correcting 1st-gen types while maintaining code quality in 2nd-gen.

[caseyisonit]

Properly reflects the types patterns we are wanting to enforce, the key update with this is NEVER using s2 in any type declarations so we avoid breaking changes in the future to remove that

[caseyisonit]

implements the as const pattern that will aid in IDE support for allowed values

[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-6067

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.

[caseyisonit]

script to auto generate contributor docs to mdx files and work in storybook. CONTRIBUTOR-DOCS remains the source of truth. ties in to yarn start/storybook so it runs when you spin up storybook

[caseyisonit]

script generates a story sort based on the directory and file structure in CONTRIBUTOR-DOCS

[caseyisonit]

rogue closing tag that broke rendering