docs: mention that `searchContent` is an experimental feature

[antfu]

🔗 Linked issue

❓ Type of change

• [x] 📖 Documentation (updates to the documentation or readme)
• [ ] 🐞 Bug fix (a non-breaking change that fixes an issue)
• [ ] 👌 Enhancement (improving an existing functionality like performance)
• [ ] ✨ New feature (a non-breaking change that adds functionality)
• [ ] ⚠️ Breaking change (fix or feature that would cause existing functionality to change)

📚 Description

mention that searchContent is an experimental feature

📝 Checklist

• [ ] I have linked an issue or discussion.
• [x] I have updated the documentation accordingly.

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View logs

[onmax]

Right now, the title is getting rendered twice:

You can use frontmatter options to render just once as the rest of markdown files in the docs. Like this:

// 7.search-content.md
---
title: 'searchContent()'
description: 'A search function in your `content` directory.'
---

::alert{type="warning"}
This is an experimental feature, opt-in with the [`experimental.search` option](/get-started/configuration#search).
::

Cannot commit directly into the branch

Result