Get the ellmer Chat Instance
get_chat_instance(mode, model, project_context, api_key, available_models)The mode of operation, one of "agent" or "ask".
The ID of the model to use (E.g., "gemini-2.5-pro").
The context of the session executing the addin, obtained with `get_project_context()`.
The API key for MyOwnRobs, obtained with `get_api_key()`.
List of available models to use.