Upgrade GitHub Actions to Node.js 24-compatible releases

[arnabnandy7]

Problem

CI workflows use outdated GitHub Actions backed by deprecated Node.js 20 or Node.js 16 runtimes. The affected action families are actions/checkout, actions/setup-java, s4u/maven-settings-action, and peter-evans/repository-dispatch.

Required outcome

• Upgrade the affected actions to published Node.js 24-compatible releases.
• Preserve existing workflow conditions, inputs, secrets, and behavior.
• Validate the workflows with static linting and confirm that no affected deprecated references remain.

Implementation

Implementation PR: #135

Related organization-wide tracking: embabel/embabel-agent#1999