action-validator `CONTRIBUTING.md` and Testing changes

The changes in this PR are based largely on those from https://github.com/mpalmer/action-validator/pull/48 (which seems to be abandoned). I have also included additional changes to support testing the Node/WASM bindings using cargo. It's not perhaps the most elegant way to do it, but it at least works as a starting point.

Mar 02 '25 15:03 bcheidemann

Since this is branched off from https://github.com/mpalmer/action-validator/pull/85, I've marked it as a draft until this is merged. I'll then rebase this PR and mark it as being ready for review.

Mar 02 '25 15:03 bcheidemann

@mpalmer this one's ready for review now

Sep 06 '25 19:09 bcheidemann

Thanks for the tidy up. As it's so extensive, it'll take me a while to do a full review, but rest assured, my eyes are on it.

Sep 08 '25 08:09 mpalmer

Thanks for the tidy up. As it's so extensive, it'll take me a while to do a full review, but rest assured, my eyes are on it.

No problem 🙂 TYT

Sep 09 '25 15:09 bcheidemann

@mpalmer thanks for the review! I have applied all of the suggestions, and pushed some commits with further improvements relating to your questions. Let me know if you'd like me to make any further changes 🙂

Oct 05 '25 10:10 bcheidemann