allow configuring theme.toc with layout: 'default' in _meta files

[dimaMachina]

reimplement #4095
closes #4036

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🦋 Changeset detected

Latest commit: 8b22b01

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

This PR includes changesets to release 3 packages

Name	Type
nextra-theme-docs	Major
nextra	Major
nextra-theme-blog	Major

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[github-actions]

📦 Next.js Bundle Analysis for swr-site

This analysis was generated by the Next.js Bundle Analysis action. 🤖

⚠️ Global Bundle Size Increased

Page	Size (compressed)
global	79.3 KB (1 B)

Details

The global bundle is the javascript bundle that loads alongside every page. It is in its own category because its impact is much higher - an increase to its size means that every page on your website loads slower, and a decrease means every page loads faster.

Any third party scripts you have added directly to your app using the <script> tag are not accounted for in this analysis

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[github-actions]

📦 Next.js Bundle Analysis for docs

This analysis was generated by the Next.js Bundle Analysis action. 🤖

This PR introduced no changes to the JavaScript bundle! 🙌