[Request]: Ollama Support

[ericrallen]

Is your feature request related to a problem? Please describe.

Add support for ollama models.

Describe the solution you'd like

If ollama is running, populate the models dropdown with available local models.

If an ollama model is selected, submit the request to the ollama model via the completion endpoint.

Additional context

We'll need to add a new ollama service with a generic model definition and adapter configuration.

We'll also need a formatting utility similar to the formatChat utility for the existing openai service.