Provide a way to retrieve raw used packages/classes before artifact mapping

### New feature, improvement proposal

AI DISCLAIMER: https://gemini.google.com/share/dd9579182da4

Currently, ProjectDependencyAnalyzer immediately aggregates scanned bytecode data into Set. When un-relocated classes exist across duplicate artifacts or fat-jars on the classpath, the artifact-guessing step yields false positives that are impossible for upstream plugins to filter cleanly.

We need an option or an extended analysis result (e.g., a getUnmappedPackages() or passing a raw Set of used types) that records the raw bytecode types detected for which no explicit top-level dependency exists before trying to associate them with a specific GAV coordinate loop.