feat: update unimport to version 4.0.0 and refactor type exports

[productdevbook]

🔗 Linked issue

❓ Type of change

• 📖 Documentation (updates to the documentation, readme, or JSdoc annotations)
• 🐞 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)
• 🧹 Chore (updates to the build process or auxiliary tools and libraries)
• ⚠️ Breaking change (fix or feature that would cause existing functionality to change)

📚 Description

I am upgrading unimport. Also toexport has been deprecated and a new version has been added. nitro v3 - main

📝 Checklist

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

[pi0]

main will be soon rebased with v2. Do you mind to open a PR for v2 for toImports migration? 🙏🏼 (also check if it is fully compatible with current version)