Result a StreamRetryCheckpoint returns: either the retry loop is
finished early with a value (the session went completed out-of-band), or
the loop should proceed to re-attempt. A checkpoint may also throw to abort
(e.g. the session reached a terminal failed/cancelled state).
Result a StreamRetryCheckpoint returns: either the retry loop is finished early with a value (the session went
completedout-of-band), or the loop should proceed to re-attempt. A checkpoint may alsothrowto abort (e.g. the session reached a terminalfailed/cancelledstate).