Function run 

pub fn run() -> Result<(), Vec<Error>>

Runs the four checks, reporting every failure rather than the first.

Prints the number of citations it resolved, so a green run says what it looked at: a check that passes silently is indistinguishable from a check that found nothing to look at, which is the failure mode §1.3.106 cost this milestone four times.

Errors

One Error per offending link, each naming the file, the line and the link. Collected rather than short-circuited, for the reason check-api-links collects them: whoever has just renamed a page wants the whole list.