feat(components): added support for all anchor attrs

[alexpricedev]

⚠️ Sorry for all of the formatting changes. I have prettier installed and I checked it was picking up the .prettierrc.yaml but on save it still seemed to want to update a load of formatting....
Main changes are:
- LOC:118-131 in packages/nuekit/src/layout/components.js
- LOC: 68-98 in CONTRIBUTING.md

Summary

This PR adds support for passing in all allowed attrs to an anchor tag (<a>). I also added some extra notes to the CONTRIBUTING.md Local Development section as it took me a few minutes to figure out the bun linking and I thought the extra notes would help other first time contributors.

The a attrs are useful for adding properties like target="_blank" to navigation items, eg:

navigation:
  footer:
    - © Nue: https://nuejs.org/
      target: _blank
      rel: noopener noreferrer

Rendered output

Notes

• Test case added
• Tests suite ran and completed with 100% pass rate

[tipiirai]

I think we should stick to compact formatting in elem() calls consistently.

[alexpricedev]

Agreed. I'll have a look at the prettier config and see if I can enforce that 👍

[alexpricedev]

I spent some time looking at this and really there isn't a good way of doing it without building a prettier plugin. I've never done that and would be up for trying it if you're interested?

[tipiirai]

The changes made here seem legit. In the future, I prefer more focused pull requests. For example, this PR should have been split in two: 1) updates to contributing 2) anchor attrs. More convenient.

But in any case: thank you for the contribution! Will merge now