Decouple CLI front-end from the assistant post

**Is your feature request related to a problem? Please describe.**
Currently, the prototype is a monolith. We should be able to decouple the CLI front-end from the rest of the service. That way we'll be able to create an new web UI in the near future.

**Describe the solution you'd like**
Decouple the CLI class from the rest of the service. Keep there only the log functions relevant to the actual CLI.

Locate the CLI class and trace how it connects to the rest of the service, noting which logging functions are specific to CLI behavior. Separate the CLI front-end while preserving those CLI-relevant logs; done means the CLI no longer depends on unrelated service responsibilities and the existing behavior still works.

Written by the indexing model from the issue text.