Split llama3 into two classes

[lordofthejars]

I think it would be great if the project would be composed with two classes, one with the API and the other with all the CLI stuff, so in case in any project we want to embed the project, we can import the class alone.

This would be a first step, probably another step would be to release it but this is another topic.

In this way, we could work in an integration between llama3 and langchain4j.