async fn log_in(state: &AppState, name: &str, block: &str) -> Result<(), String>Expand description
Log in to SSH host name (a known_ssh_host) and run true, with
ssh’s prompts going to the user in the window of pane block, if any.
The connection’s status follows (link::login), and the connection stays
up a while after (ControlPersist), so the next pane on it asks nothing.