ci: chromatic runs for S2 [CSS-1233]

[castastrophe]

Description

• Chromatic configuration is updated to support running Visual Regression Tests (VRT) against the spectrum-two branch
• VRT runs are automated and triggered on all pull requests targeting spectrum-two
• Results are properly reported and accessible to the team
• Documentation is updated to reflect the new configuration

Why?

We need to enhance our Chromatic configuration to support automated VRT for pull requests targeting the spectrum-two branch. This will help us catch visual regressions early in the development process and ensure visual consistency across our components as we work on Spectrum 2 migrations.

How and where has this been tested?

Please tag yourself on the tests you've marked complete to confirm the tests have been run by someone other than the author.

Validation steps

1. Create a test PR targeting the spectrum-two branch
2. Push changes that would trigger a visual difference
3. Verify that Chromatic automatically:
   • Runs the VRT process
   • Generates comparison results
   • Reports results in the expected location
4. Verify that the baseline comparisons are made against spectrum-two
5. Confirm that results are properly accessible to team members

To-do list

• I have read the contribution guidelines.
• If my change impacts documentation, I have updated the documentation accordingly.
• ✨ This pull request is ready to merge. ✨

[castastrophe]

This property is deprecated and no longer supported so I removed it.

[github-actions]

📚 Branch preview

PR #4070 has been deployed to Azure Blob Storage: https://spectrumcss.z13.web.core.windows.net/pr-4070/index.html.

[github-actions]

File metrics

Summary

Total size: 1.44 MB^*

🎉 No changes detected in any packages

* Size is the sum of all main files for packages in the library.
* An ASCII character in UTF-8 is 8 bits or 1 byte.

[changeset-bot]

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Latest commit: f11fa47

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