refactor: clarify runtimes and `isNode` behavior

[pi0]

🔗 Linked issue

closes #100

❓ 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

📝 Checklist

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

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Comparison is base (3250631) 80.63% compared to head (381069c) 82.50%.

:exclamation: Current head 381069c differs from pull request most recent head bec505d. Consider uploading reports for the commit bec505d to get more accurate results

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #108 +/- ## ========================================== + Coverage 80.63% 82.50% +1.87% ========================================== Files 10 10 Lines 346 383 +37 Branches 32 32 ========================================== + Hits 279 316 +37 Misses 61 61 Partials 6 6 ```

:umbrella: View full report in Codecov by Sentry.
:loudspeaker: Have feedback on the report? Share it here.