feat(rollup): add support for generating build meta

[jrson83]

🔗 Linked issue

#235

❓ 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

Add support for generating build metadata in JSON format to visualize with Bundle Buddy.

Resolves #235

Example screenshot of unbuild's metadata on Bundle Buddy

📝 Checklist

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

[jrson83]

@pi0 if something missing let me know. Should be all good.

[pi0]

Hi dear @jrson83 sorry again on my late response on this.

I think this is a nice implementation for good start. Looking at bundle-buddy, seems this project is in experimental state for long time. I like to investigate little bit more if we can introduce multiple bundle analyze formats at once for different tooling compatibility. Defenitly something i am looking forward to happen 👍🏼

[jrson83]

@pi0 that would be a great addition. Looking forward hearing from you.