Add automated release workflow

[BowTiedRadone]

This PR adds a GitHub Actions workflow to automate the release process for the Hedgehog library. Key features:

• Builds and packages the Hedgehog library using the latest GHC and cabal-install via GHCup.
• Uses cabal sdist to generate the tarball matching maintainer/Hackage requirements.
• Checks the package with cabal check before upload.
• Uploads the tarball to Hackage using a repository secret (HACKAGE_TOKEN).
• Only triggers on new tags.

Notes

The workflow expects a valid HACKAGE_TOKEN secret to be set in the repository for Hackage uploads. The tarball creation logic is designed to match the official Hackage release process as closely as possible.

Considerations

The new workflow's output was tested locally using act and diff-checked agains the latest official Hackage release. This PR should be merged after one of the maintainers can confirm the HACKAGE_TOKEN secret addition.

[moodmosaic]

We can generate and add one. Before we do that, we need to make sure that the Actions permissions are set to the minimal needed for each workflow/job, to avoid hijacking.

[BowTiedRadone]

Yes. I recommend this action to at least require an approval from a GitHub account with write access.

[moodmosaic]

Thank you @BowTiedRadone!

We can simplify the workflow by using cabal sdist, and speed up the checkout by doing a shallow clone (fetch-depth: 1).

[BowTiedRadone]

I think the last discussion item for this PR is the fact that it uses ubuntu-22.04, while #558 just updated haskell-ci workflow to use ubuntu-24.04. Should we update this workflow to use ubuntu-24.04 as well?

[moodmosaic]

I think the last discussion item for this PR is the fact that it uses ubuntu-22.04, while #558 just updated haskell-ci workflow to use ubuntu-24.04. Should we update this workflow to use ubuntu-24.04 as well?

Yes, that's a good point 👍

[moodmosaic]

LGTM. Thank you for your contribution! I’m curious to know what @vrom911 and/or @chshersh think (if their time permits). 🙏

[moodmosaic]

@BowTiedRadone, what would be the easiest way to test this?

[BowTiedRadone]

@moodmosaic The easiest would be cutting a test tag (since the workflow does not publish anyway). The other way would be to use https://github.com/nektos/act for local debugging. For the second, I can share the steps if needed.