Expose model configuration to the frontend

Problem/Motivation

After ✨ Rebase on AI module's abstraction layer Active is done, configuration form could also be exposed to the frontend allowing to fine-tune configuration inline as user is having a conversation.

Proposed resolution

Add AI model configuration form to 'conversation' form under 'Additional settings'. Since backend and frontend are separate, it may require for frontend to expose new special methods which backend could use and set the form.

Developer should be able to configure what settings should be available on the frontend and for what user roles.

Remaining tasks

User interface changes

API changes

Data model changes