Add Checkstyle Plugin to Enforce Import Rules

[dariuszzbyrad]

While analyzing the project, I found several unused and redundant import statements. To improve the code quality and ensure that best practices are followed going forward, I have added the Checkstyle plugin with rules to:

• Detect and remove unused imports.
• Prevent redundant imports (e.g., duplicate imports of the same class).
• Disallow illegal imports such as sun.* packages by default.

This configuration will help maintain clean and compliant code, and the build will fail if any violations are detected.

[FDelporte]

Thanks @dariuszzbyrad! I'm all in favor of cleaner code, so this looks great. Asking for second opinion to Tom and/or Eitch so we can merge this.

[taartspi]

 Thanks, this is a good idea to help keep the code clean.    You created a new _config_ directory with the context _checkstyle_.   Do you see more config file types  are possible and these separate directories are needed ?           Tom

[dariuszzbyrad]

Yes, potentially at the config level, we could add tools like CodeNarc, PMD, SpotBugs, etc. Additionally, for Checkstyle specifically, we might include files like suppressions.xml and suppressions-cpath.xml to manage specific rule exceptions.

[taartspi]

Thanks for the response and the PR. Tom

[eitch]

The issue looks fine, but we have to bear in mind, that our resources are limited. Adding new checks and then failing the build should not be a priority. I am always willing to look at PRs with new checks, where each new check is a new PR and the build doesn't fail with the new check.

If we can agree on this, then i find this a good change and am always for cleaner and better code.

[eitch]

This looks good