feat(mcp): add tool to update registry

feat(gen): jni supports externs and interfaces

adjust filters to support externs and referenced interfaces

filters(jni): add empty return of java type

in case a native function implemented in cpp fails and is not able
to deliver the result, we don't want to allocate a java type from cpp,
we return the nullptr for object-like types.

feat(ue): add support to reference interfaces

refactor(ue): rename enums to pascalcase