Improve interface and implementation support in jump actions

[RoiSoleil]

The "Jump to Test/Code" functionality in MoreUnit now better supports interfaces and their implementations.

Key changes:

1. Supertypes Search: When searching for tests for a class, MoreUnit now also considers tests for its superclasses and interfaces (excluding java.lang.*). This allows jumping from a class like FooImpl to FooTest if FooImpl implements Foo.
2. Implementation Discovery: When searching for the code under test from a test class, MoreUnit now includes concrete implementations of any matched interface or abstract class.
3. Refined UX for Interfaces: To avoid jumping to "empty" interfaces when concrete code exists, MoreUnit will now exclude interfaces or abstract classes from the jump targets if:
   • At least one concrete implementation was found.
   • The interface/abstract class itself contains no non-abstract methods (e.g., no default methods in an interface).
4. Unit Tests: Added InterfaceCorrespondingTypeSearcherTest to verify these navigation scenarios.

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PR created automatically by Jules for task 18132929899494660556 started by @RoiSoleil

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[RoiSoleil]

ok

[codecov]

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