#2033: Added UML diagrams for the GUI

[laim2003]

This PR fixes #2033

Implemented changes:

• Added comprehensive PUML diagrams for the GUI structure.

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Testing instructions

• No testing required, only documentation updated.

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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.
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  with internal
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[coveralls]

Coverage Report for CI Build 27631907653

Coverage decreased (-0.03%) to 71.255%

Details

• Coverage decreased (-0.03%) from the base build.
• Patch coverage: No coverable lines changed in this PR.
• 2 coverage regressions across 2 files.

Uncovered Changes

No uncovered changes found.

Coverage Regressions

2 previously-covered lines in 2 files lost coverage.

File	Lines Losing Coverage	Coverage
com/devonfw/tools/ide/tool/ide/IdeToolCommandlet.java	1	78.33%
com/devonfw/tools/ide/version/VersionSegment.java	1	89.76%

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Coverage Stats

Relevant Lines:	16222
Covered Lines:	12054
Line Coverage:	74.31%
Relevant Branches:	7250
Covered Branches:	4671
Branch Coverage:	64.43%
Branches in Coverage %:	Yes
Coverage Strength:	3.15 hits per line

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💛 - Coveralls

[KarimALotfy]

Great job! The UML diagram is clean, easy to follow, and provides a clear and informative overview of the flow