feat(thumbnail-opacity-checkboard): S2 migration

[cdransf]

Description

CSS-1056

This is a follow up to CSS-1023, implementing the thumbnail-opacity-checkerboard-square-size that is specific to the thumbnail component but targeted at the opacity-checkerboard.

Adds thumbnail specific --spectrum-opacity-checkerboard-size token. This impacts the display of the opacity-checkerboard when used within the thumbnail component.

Validation steps

1. Run Storybook locally or open the link for the PR.
2. Navigate to the thumbnail component.
3. Verify that no regressions are visible.

Regression testing

Validate:

1. The documentation pages for at least two other components are still loading, including:

• The pages render correctly, are accessible, and are responsive.

2. If components have been modified, VRTs have been run on this branch:

• VRTs have been run and looked at.
• Any VRT changes have been accepted (by reviewer and/or PR author), or there are no changes.

To-do list

• I have read the contribution guidelines.
• I have updated relevant storybook stories and templates.
• I have tested these changes in Windows High Contrast mode.
• If my change impacts other components, I have tested to make sure they don't break.
• If my change impacts documentation, I have updated the documentation accordingly.
• ✨ This pull request is ready to merge. ✨

[changeset-bot]

🦋 Changeset detected

Latest commit: 87bbb9c

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 3 packages

Name	Type
@spectrum-css/thumbnail	Major
@spectrum-css/table	Major
@spectrum-css/treeview	Major

Not sure what this means? Click here to learn what changesets are.

Click here if you're a maintainer who wants to add another changeset to this PR

[github-actions]

File metrics

Summary

Total size: 4.29 MB^*
Total change (Δ): ⬆ 0.50 KB (0.01%)

Table reports on changes to a package's main file. Other changes can be found in the collapsed Details section below.

Package	Size	Δ
thumbnail	7.80 KB	⬆ 0.13 KB

Details

thumbnail

File	Head	Base	Δ
index-base.css	7.80 KB	7.67 KB	⬆ 0.13 KB (1.71%)
index-vars.css	7.80 KB	7.67 KB	⬆ 0.13 KB (1.71%)
index.css	7.80 KB	7.67 KB	⬆ 0.13 KB (1.71%)
metadata.json	3.64 KB	3.55 KB	⬆ 0.10 KB (2.70%)

* Size determined by adding together the size of the main file for all packages in the library.
* Results are not gzipped or minified.
* An ASCII character in UTF-8 is 8 bits or 1 byte.

[github-actions]

🚀 Deployed on https://pr-3394--spectrum-css.netlify.app