#2129: cleanup mvnd from review from PR #2061

[Hiepiscus]

This PR fixes #2129

This PR addresses the remaining review comments from PR #2061 that were intentionally left unimplemented because the original author is no longer available.

The focus of this cleanup is the auto-completion implementation. Since several completions are not specific to mvnd, common maven related completions have been moved to super class implementation to avoid duplication.

Implemented changes:

• Moved Maven common auto-completion entries from mvnd specific code to MavenCommandlet super class.
• added a new method AutoCompletionRegistry.add(String candidate, String synonym)

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Testing instructions

1. Run ide shell
2. type install mvnd -> tool should be installed successfully
3. After successfull installation type mvnd --version -> the version installed should be displayed
4. Verify that mvnd auto-completion works mvnd <TAB> <TAB> -> expect to still display the arguments e.g. --settings
5. Verify that mvn auto-completion works mvn <TAB> <TAB> -> expect to display the arguments as well e.g. --settings`

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Checklist for this PR

Make sure everything is checked before merging this PR. For further info please also see
our DoD.

• When running mvn clean test locally all tests pass and build is successful
• PR title is of the form #«issue-id»: «brief summary» (e.g. #921: fixed setup.bat). If no issue ID exists, title only.
• PR top-level comment summarizes what has been done and contains link to addressed issue(s)
• PR and issue(s) have suitable labels
• Issue is set to In Progress and assigned to you or there is no issue (might happen for very small PRs)
• You followed all coding conventions
• You have added the issue implemented by your PR in CHANGELOG.adoc unless issue is labeled
  with internal
• You have formulated clear instructions on how to test your contribution under "Testing instructions"

[coveralls]

Coverage Report for CI Build 29480084012

Warning

No base build found for commit a88c41e on main.
Coverage changes can't be calculated without a base build.
If a base build is processing, this comment will update automatically when it completes.

Coverage: 72.193%

Details

• Patch coverage: No coverable lines changed in this PR.

Uncovered Changes

No uncovered changes found.

Coverage Regressions

Requires a base build to compare against. How to fix this →

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Coverage Stats

Relevant Lines:	16735
Covered Lines:	12590
Line Coverage:	75.23%
Relevant Branches:	7464
Covered Branches:	4880
Branch Coverage:	65.38%
Branches in Coverage %:	Yes
Coverage Strength:	3.18 hits per line

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💛 - Coveralls

[Caylipp]

Good job! I reviewed the changes and manually tested the mvnd auto-completion in both the regular terminal and the IDEasy shell. The expected suggestions, including --settings, are displayed correctly.
Please also update the .gitignore, this item is still unchecked. 👍