fix: make release dry-run checks executable

[bmarwell]

Fixes #244.

• Detect the Maven release plugin from the effective POM without suppressing its output or triggering a pipefail SIGPIPE.
• Run release:prepare in batch mode for non-interactive dry runs.
• Align JReleaser validation and documentation with jreleaser.toml.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 72.11%. Comparing base (caa4e09) to head (5d71841).
⚠️ Report is 1 commits behind head on main.
✅ All tests successful. No failed tests found.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #246   +/-   ##
=======================================
  Coverage   72.11%   72.11%           
=======================================
  Files          26       26           
  Lines         563      563           
  Branches       52       52           
=======================================
  Hits          406      406           
  Misses        128      128           
  Partials       29       29           

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[Copilot]

Pull request overview

This PR updates the release dry-run verification script and related documentation to correctly detect required Maven/JReleaser configuration and run non-interactively, aligning the process with the repository’s jreleaser.toml setup.

Changes:

• Fix Maven release plugin detection by inspecting the effective POM without quiet mode and without grep -q (to avoid pipefail/SIGPIPE issues).
• Run mvn release:prepare in batch mode (-B) to keep dry-runs non-interactive.
• Update release documentation/comments to reference jreleaser.toml instead of the retired jreleaser.yml.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

File	Description
test-release.sh	Adjusts dry-run checks: effective POM inspection, batch-mode release prepare, and TOML config file validation.
RELEASING.adoc	Updates troubleshooting guidance to reference jreleaser.toml.
cli/pom.xml	Updates an explanatory comment to reference jreleaser.toml distribution expectations.