Function user_turn 

pub fn user_turn(
    state: &str,
    question: Option<&str>,
    options: &[(&str, &str)],
) -> String

Build the user turn: context, question, lettered options, and a closing reminder.

The reminder after the options repeats the instruction because it is the text nearest the generation point, which is where a small model is most likely to still be following it.