Preserve exact dependency class names containing dollar signs

[wilx]

Fixes apache/maven-dependency-plugin#1345

Summary

Preserve exact JVM binary class names when collecting dependency usages and dependency artifact contents.

The analyzer previously assumed that every $ in a binary class name denoted an inner class and discarded or folded that name into its presumed container. Kotlin can emit bytecode that references only a nested class, so the corresponding artifact was incorrectly reported as unused. The assumption was also invalid for legal top-level Java class names containing $.

Artifact lookup already deduplicates usages by artifact, so retaining the exact binary name correctly handles both nested classes and top-level names without independently inferring the source-level compilation unit.

The change adds:

• a Kotlin integration test reproducing the nested-class-only reference;
• an integration test for a genuine top-level Java class containing $;
• unit coverage for exact usage collection and exploded dependency directories.

Verification

• mvn -Prun-its verify with JDK 17: 128 unit tests and all 21 invoker builds passed.
• Focused Kotlin and top-level-dollar integration tests passed with JDK 8 and JDK 17.
• The original Dropwizard/Kotlin reproducer completed without dependency-analysis warnings.

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