feat: workflow to automatically update java format + create PR

[russellwheatley]

• Adds a cron job GitHub Actions workflow that checks for new google-java-format releases, updates the bundled JAR in lib/, rewrites the hardcoded JAR path in index.js, runs ./test.sh, and opens a PR automatically when an upstream update is available.
• Also adds workflow_dispatch to the existing test workflow so CI can be run manually on the generated update branch/PR without requiring a PAT.

[gemini-code-assist]

Note

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