* Control: a timeout says whether the command ran (#3662)
A request still queued when its deadline passes is dropped before
dispatch, but it answered with the same text as the transport giving up
on a command that may still apply. The two now read differently: "timeout:
not run ... safe to re-send" and "timeout: no reply in 60s ... may still
apply", both keeping the `timeout` prefix machines match on.
* Control: a transport that gives up knows whether the command was dispatched (#3662)
The transport and the UI thread share the reply deadline, and the
transport's wait runs out first, so the UI thread's "not run" reply
almost never reached a client. A request now carries a dispatch flag
settled once between them: the UI thread claims it before running, the
transport abandons it when it stops waiting. The transport then replies
"not run" for a request that will never run, and "may still apply"
only for one that was dispatched; a request given up on is never run.
Marco Arnulfo
8145bea70f