docs: add @shikiji/vitepress-twoslash

[sapphi-red]

Description

Added @shikijs/vitepress-twoslash so that users can hover the code to know the types. I didn't add to some code blocks for those I thought it will be distracting.
https://deploy-preview-16168--vite-docs-main.netlify.app/guide/api-javascript.html#build

BTW it was really easy to add this. It's awesome.

Additional context

---

What is the purpose of this pull request?

• Bug fix
• New Feature
• Documentation update
• Other

Before submitting the PR, please make sure you do the following

• Read the Contributing Guidelines, especially the Pull Request Guidelines.
• Check that there isn't already a PR that solves the problem the same way to avoid creating a duplicate.
• Provide a description in this PR that addresses what the PR is solving, or reference the issue that it solves (e.g. fixes #123).
• Update the corresponding documentation if needed.
• Ideally, include relevant tests that fail without this PR but pass with it.

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[bluwy]

Love it 🤌

[patak-dev]

Woah... this looks so good 😍