Add tool-versions file

[ThisIsMissEm]

This helps software like asdf discover exactly what version of hugo to use, since hugo versions often have incompatibilities.

I've been bitten many times working on docs but having the wrong version of hugo in my $PATH

[ThisIsMissEm]

Added comments to try to keep this in sync, since we can't reuse the tool-versions file in GitHub Actions directly

[ClearlyClaire]

I'm not familiar with asdf so I'm not sure if that is something we want to support/encourage, but if we do, this PR looks good to me.

[ThisIsMissEm]

@ClearlyClaire the main reason I ended up using asdf for Hugo was because I contribute to multiple Hugo sites each running different incompatible versions, so I'd constantly get weird breakages when switching between repos. asdf helps with that by automatically switching my hugo version to the right one for the project & the .tool-versions file in the root of the repo acts as a bit of a guide as to what we use.

[mjankowski]

FYI, you can do something like...

echo ".tool-versions" >> .git/info/exclude

...which will let you get the benefits of asdf locally, w/out needing the project to adopt it or add to their gitignore.

[ThisIsMissEm]

I'd be of the inclination to suggest we do adopt .tool-versions here, not necessarily to say adopt asdf, but rather to have a file in the root of the repository that does contain the version required.

[mjankowski]

Yes, agreed on having it better locked/specified somewhere.

Im guessing theres no equivalent of .nvmrc or .ruby-version for hugo projects? Also, its too bad the format here with extended doesnt quite match the format needed in the CI config...

[ThisIsMissEm]

Also, its too bad the format here with extended doesnt quite match the format needed in the CI config...

Yeah, that annoys me too, but there isn't really anything we can do about that, unless we do an upstream PR to the github action to support .tool-versions syntax?

[mjankowski]

Sort of related - https://github.com/peaceiris/actions-hugo?tab=readme-ov-file#%EF%B8%8F-read-hugo-version-from-file - the GH action that publishes the site could pull that version value from a file (example there is a .env, but in theory could do whatever)