Kotlin, Java language support

[hossihub]

It would be very valuable to add first-class support for Kotlin and Java projects, alongside the currently supported languages. Since many modern JVM-based systems are built with Kotlin and Java, this would significantly expand LeanKG’s usefulness.

Specifically, support for:

Parsing Kotlin and Java ASTs (classes, functions, interfaces, imports)
Resolving cross-language relationships in mixed JVM projects (Kotlin ↔ Java interop)
Indexing Gradle/Maven-based project structures
Basic symbol/dependency graph generation for both languages

This would make LeanKG much more applicable in enterprise and backend environments where JVM ecosystems dominate.

[linhdmn]

Thanks, I'm working on this shortly, when this issue closed, this will mean Kotlin and Java fully supported

[pkurcx]

@linhdmn I'd add Scala to these two as well

[linhdmn]

That'd be great too @pkurcx