fix: scan env specific handlers without method in their name

[sandros94]

🔗 Linked issue

Resolves #2850

❓ 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

Switching to named capture groups within the regex both simplifies the maintenance of its implementation as well as directly creates a binding between the regex's named groups and the related method and env variables.

P.S.: having troubles with my dev machine, didn't run pnpm dev/pnpm test, but it is such a small fix (famous last words).

📝 Checklist

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