chore: add binary caching

[agarvin-nr]

Summary

• Caches GoReleaser binaries

Validation

• Adds a step which validates whether dist files exist (whether cached or fresh):
  • Verifies that metadata files exist (artifacts.json and metadata.json)
  • Verifies that binary files exist
  • Verifies that archive and package files exist, and validates their checksums
• Run workflows in GitHub twice (with and without caching)

[agarvin-nr]

Trying a hard stop if metadata isn't found in the cached build, following this discussion on the original draft.

[agarvin-nr]

Given that CI only uses a single arch, is checking for all binaries like this overkill?

If so, we may only need to check for metadata.json here - We do a separate check for the specific arch's binary in a later step.

[mailo-nr]

I think runner.temp might handle this already: https://docs.github.com/en/actions/reference/workflows-and-actions/contexts#runner-context

[agarvin-nr]

That sounds much nicer, I'll look into that, thank you!

[mailo-nr]

What are your thoughts on moving this to its own bash script? Since it's just a sanity check if might make sense to not clutter the workflow.

[agarvin-nr]

Putting it in its own bash script sounds much better to me! We might be able to re-use it for other workflows in the future that way.

I can do the same for the Verify source files exist step too, since it's a similar sanity check.

[mailo-nr]

Looks good