Add release workflow for 'latest' tag

[google-labs-jules]

Added a GitHub Actions workflow .github/workflows/release.yml that:

1. Triggers on release published events.
2. Filters execution to only run when the release tag is latest.
3. Sets up Java 21 and caches Maven packages.
4. Builds the project using mvn -B package with -Dproject.branch=latest.
5. Uploads the generated JAR file to the release using the gh CLI.

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PR created automatically by Jules for task 9876017673702413788 started by @SjnExe

[google-labs-jules]

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