feat: preserve and make error cause accessable

[pi0]

🔗 Linked issue

Resolves #377

❓ 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

This PR improves H3Error class with a polyfill to support v8 error cause universally.

The createError wrapper also always provides input (or input.cause if provided) as cause so we can always access original error/object.

Another small fix: onError types fixed. It accepts an H3Error.

📝 Checklist

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

[codecov]

Codecov Report

Merging #479 (7c0048b) into main (9a57a89) will increase coverage by 0.12%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main     #479      +/-   ##
==========================================
+ Coverage   80.01%   80.13%   +0.12%     
==========================================
  Files          27       27              
  Lines        3027     3036       +9     
  Branches      453      454       +1     
==========================================
+ Hits         2422     2433      +11     
+ Misses        605      603       -2     

Files Changed	Coverage Δ
src/app.ts	97.95% <100.00%> (ø)
src/error.ts	80.44% <100.00%> (+1.03%)	⬆️

... and 1 file with indirect coverage changes