Function act_now_many 

fn act_now_many(
    qt: &CxxQtThread<Sioul>,
    shared: &Arc<Shared>,
    found: Vec<(Account, PathBuf)>,
    remote: Vec<(Account, ServerRef)>,
    action: Action,
)

Reading and flagging several messages: shown at once, then each account’s server told in one connection; put back where it refuses.