Fix synced nested <Tabs> restoration issue

[HiDeoo]

Description

This pull request fixes an issue reported on Discord regarding synced nested tabs.

Repro steps:

• Visit https://developers.cloudflare.com/d1/get-started/#1-create-a-worker
• Select the Dashboard tab
• Reload the page
• The first tab panel is invisible

This issue is similar to #473 where the panels hidden property was not being set correctly due to the query selector matching all nested panels instead of just the direct children. The same issue can happen when restoring synced tabs as this part of the code was not including the same fix.

The restoration code now also uses the :scope CSS pseudo-class to only match the direct children.

I've included a test case to cover both the syncing of nested tabs (fixed in #473) and the restoration of synced nested tabs (fixed in this PR).

I also tested the fix locally on the Cloudflare docs and it now works as expected.

[changeset-bot]

🦋 Changeset detected

Latest commit: 33e0e4e

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

This PR includes changesets to release 1 package

Name	Type
@astrojs/starlight	Patch

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[delucis]

Thanks for fixing so quickly @HiDeoo! Will get this released right away for folks 🫡