fix: add Nitro hooks types declarations

[Coiggahou2002]

🔗 Linked issue

2177

❓ Type of change

• [ ] 📖 Documentation (updates to the documentation or readme)
• [x] 🐞 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

Resolves #2177 by augmenting the NitroRuntimeHook typing to provide typings of hook content:beforeParse and content:afterParse (and also IDE intellisense of course)

📝 Checklist

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