Assign a task (objective + checklist of action items) to the agent.
Summary
Types
@type action_item() :: Guava.SerializableField.t() | Guava.Say.t() | Guava.Todo.t()
@type t() :: %Guava.Commands.SetTask{ action_items: [action_item()], command_type: String.t(), completion_criteria: String.t() | nil, objective: String.t(), task_id: String.t() }