#756: Add tests for CustomToolRepository using WireMock

[vivu001]

This PR fixes #756

Implemented changes:

• Improve test coverage by adding tests for CustomToolRepository

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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)
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  with internal

[coveralls]

Coverage Report for CI Build 27673466541

Coverage increased (+0.4%) to 71.694%

Details

• Coverage increased (+0.4%) from the base build.
• Patch coverage: No coverable lines changed in this PR.
• 3 coverage regressions across 2 files.

Uncovered Changes

No uncovered changes found.

Coverage Regressions

3 previously-covered lines in 2 files lost coverage.

File	Lines Losing Coverage	Coverage
com/devonfw/tools/ide/version/VersionSegment.java	2	90.03%
com/devonfw/tools/ide/tool/ide/IdeToolCommandlet.java	1	78.33%

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Coverage Stats

Relevant Lines:	16222
Covered Lines:	12120
Line Coverage:	74.71%
Relevant Branches:	7250
Covered Branches:	4708
Branch Coverage:	64.94%
Branches in Coverage %:	Yes
Coverage Strength:	3.16 hits per line

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💛 - Coveralls

[Caylipp]

The test suite looks well structured and comprehensive. Good job 👍
I tested with mvn clean test and all tests run successfully!

The Arrange/Act/Assert pattern is used consistently and the scenarios are clearly separated.
Overall, very clean and solid test coverage.