Function move_contact 

pub(crate) fn move_contact(
    qt: &CxxQtThread<Sioul>,
    shared: &Arc<Shared>,
    key: &str,
    book: &str,
    confirmed: bool,
) -> String

A contact moved to another address book: written there, then taken out here. When the book would not keep something the card holds, nothing moves until confirmed: returns {"losses": [words]}, else {"key"} or {"error"}.