feat: check `MODE` variable for isDevelopment and isProduction flags

[markflorkowski]

🔗 Linked issue

Currently n/a, can open an issue as well if you want me to.

❓ Type of change

• [ ] 📖 Documentation (updates to the documentation, readme, or JSdoc annotations)
• [ ] 🐞 Bug fix (a non-breaking change that fixes an issue)
• [x] 👌 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

Utilize the MODE environment variable to check if we are in development or production in addition to other checks from before.

The MODE environment variable is used in Vite to differentiate running in development or production.

📝 Checklist

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