Allow Goose to be able to change its own model for you

[amayers]

Please explain the motivation behind the feature request.
Goose supports using models from many different sources. However finding and configuring them is a tedious task that requires that I know the exact source & model name to put into the UI. So I figured I'd ask Goose to change it's model for me. But it's unable to.

Describe the solution you'd like
I should be able to tell Goose to change it's model to be the best one, or the best one for a specific set/type of tasks, and it would do that instead of manually making me figure out how to do it.

Describe alternatives you've considered
Goose doesn't use a single model at all. Instead it evaluates every request and decides on the best model for that specific request.

Additional context

• I have verified this does not duplicate an existing feature request