Enable text-autospace in Chinese and Japanese documents

[tats-u]

Description

• Closes Enable `text-autospace` CSS property in Chinese and Japanese documents in Starlight like VitePress and Rspress #3871

Especially in Chinese and Japanese, the CSS property text-autospace: normal is preferred for better looking like books by automatically inserting spaces with the moderate width.

• https://developer.chrome.com/blog/css-i18n-features#inter-script_spacing_text-autospace
• https://developer.mozilla.org/docs/Web/CSS/text-autospace
• https://webkit.org/blog/16574/webkit-features-in-safari-18-4/#:~:text=Text%20auto%20space
• Enable text-autospace for CJK languages vuejs/vitepress#4996
• feat(theme): add text-autospace: normal; web-infra-dev/rspress#2920
• https://github.com/web-infra-dev/rspress/releases/tag/v2.0.0-rc.3

Without this, some users and AIs try to insert such spaces manually as workarounds but they are too wide and prevent keywords from searched.

Japanese:

Before:

After:

Note: the current Chinese content of Starlight translation is not affected because it took the workarounds like manually inserting spaces.

The other languages are not affected.

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🦋 Changeset detected

Latest commit: ae8d92d

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

This PR includes changesets to release 1 package

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[delucis]

Thanks @tats-u — this looks good to me. Just one small changelog suggestion.

[tats-u]

Based on your feedback, I have updated the changeset description.

[delucis]

Thanks again @tats-u! We’ll get this released in our next minor.