Publish GitHub releases automatically from main

[PrestaSafe]

Summary

Publish the installable PrettyBlocks ZIP as a GitHub Release after a successful build on main.

• create a tag and release matching the version declared in prettyblocks.php
• keep the existing tag convention without a v prefix
• attach prettyblocks.zip and its SHA-256 checksum
• generate the changelog with GitHub's release-notes API
• prepend a deduplicated contributor list derived from the commits since the previous release
• skip safely when the release for the current module version already exists
• grant contents: write only to the publication job

Pull requests and manual workflow dispatches continue to build artifacts without publishing a release.

Why

The current workflow uploads an Actions artifact retained for 14 days, but does not create a tag or an entry in the repository's Releases page. Consequently the merged 3.2.1 compatibility work is built successfully but is not yet available as a durable GitHub Release.

Once this PR is merged, its push to main will build the package and publish release 3.2.1, because neither that tag nor that release currently exists.

Contributor attribution

GitHub's generated preview lists the merged pull requests but not the authors of the cherry-picked fixes. The additional contributor section restores those commit-level credits. The current 3.2.1 range resolves to:

• Benoit Charpentier
• Guillaume Batier
• Jonathan Danse

Validation

• actionlint .github/workflows/build-release.yml
• scripts/build-release.sh
• module version resolved as 3.2.1
• previous release resolved as 3.2.0
• release/tag absence checked for 3.2.1
• contributor and checksum generation simulated locally
• generated ZIP SHA-256: 0b115fba49191a9b94d3852004654a2627bf3211e9c6c3c7bcb32beca2dfe2b2