#2131: improve auto completion for ide upgrade mode

[vivu001]

This PR fixes #2131

Implemented changes:

• Added enum-based auto-completion support for CLI parameters using EnumProperty
• Implemented value suggestions for --mode in UpgradeCommandlet
• Enabled prefix-based filtering for parameter values (e.g. --mode=s)
• Ensured completion output follows IDEasy token-based behavior (--key=value)
• Added user-facing documentation for parameter value completion in CLI docs

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Testing instructions

1. Checkout the feature branch.
2. Run the following script to build the native image: ./build-local-dev.sh.
3. Start a new terminal session
   Ensure the newly built executable is picked up (restart shell if needed).
4. Verify auto-completion suggestions: open a bash terminal, then run:

• Case 1:

ide upgrade --mode=[Tab][Tab]

Expected output:
--mode=snapshot --mode=stable --mode=unstable

The suggested values correspond to all predefined values of the UpgradeMode enum.

• Case 2: Verify prefix filtering

ide upgrade --mode=s[Tab][Tab]

Expected output:
--mode=snapshot --mode=stable

• Case 3: Verify direct completion

ide upgrade --mode=st[Tab]

Expected output: the command is automatically completed with the matched value.
ide upgrade --mode=stable

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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 29899764810

Coverage increased (+0.04%) to 72.537%

Details

• Coverage increased (+0.04%) from the base build.
• Patch coverage: No coverable lines changed in this PR.
• No coverage regressions found.

Uncovered Changes

No uncovered changes found.

Coverage Regressions

No coverage regressions found.

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Coverage Stats

Relevant Lines:	16965
Covered Lines:	12831
Line Coverage:	75.63%
Relevant Branches:	7588
Covered Branches:	4979
Branch Coverage:	65.62%
Branches in Coverage %:	Yes
Coverage Strength:	3.2 hits per line

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💛 - Coveralls

[oanding-blrng]

I was able to test the implemented auto-completion and can confirm that the described behaviour. After the suggestions this PR can move forward.

Example from my terminal after execution of `./build-local-dev.sh`.

[oanding-blrng]

Please also change the title of this PR to follow the rules of DoD:

PR title is of the form #«issue-id»: «brief summary» (e.g. #921: fixed setup.bat). If no issue ID exists, title only.

[oanding-blrng]

This pr can move forward. The changes are looking fine and the suggestions are applied.