Multi-turn conversation value type. Bind one to a signature input field whose Zoi type is Dsxir.Primitives.History; the chat adapter materializes the conversation into the prompt sequence.

Distinct from Dsxir.History (the inspect_history developer tool). The name overlap mirrors DSPy's dspy.History (the value type) and dspy.inspect_history (the debug helper).

Entries are plain maps to keep the struct cheap and serializable:

%Dsxir.Primitives.History{
  messages: [
    %{role: :user, content: "What is the capital of France?"},
    %{role: :assistant, content: "Paris."}
  ]
}