Function ack_engineer 

pub fn ack_engineer(
    home: &Path,
    cwd: &str,
    shown: &[&Message],
    now: i64,
) -> Result<()>

Acknowledges, as the engineer of the repo at cwd (engineer:<git user.email>), the messages to the engineer among shown, which a view put in front of them, that no Seen of theirs on this node lists yet (engineer_acks): the terminal inbox calls it, and so may any view that shows the engineer a message’s text (borg top, borg web).

Errors

A write failure.