mesh-issues: say a delivered fix left in fixing, and flag a stale claim (hq issue 483)

The operator found 13 issues in fixing whose fix was delivered hours before:
their pull requests were linked, not in fixed-by, so their delivery was never
measured, and nothing said an issue left there or a worker gone.

modules/mesh-issues/cmd/mesh-issues/worker.go

@@ -90,7 +90,9 @@ type workOutcome struct {
 	took     bool   // a worker started, or the issue changed hands
 	from     string // the worker it was taken over from
 	wasStale bool   // the worker taken over from was stale
-	released string // the worker whose work ended, on a move to a status that has none
+	// staleClaim is a stale worker with no pull request open: a claim nobody works on (novox/hq issue 483).
+	staleClaim bool
+	released   string // the worker whose work ended, on a move to a status that has none
 }
 
 // workerFor applies a move's worker to an issue, under ADR 0283 §1 and §2: another worker not stale is refused
@@ -121,6 +123,7 @@ func workerFor(is *Issue, to, by, takeOver string, now time.Time, staleAfter tim
 		return out, nil
 	}
 	out.wasStale = cur.stale(now, staleAfter)
+	out.staleClaim = out.wasStale && !openPullRequest(is)
 	if !out.wasStale && takeOver == "" {
 		return out, fmt.Errorf("%s works on issue %d (%s) since %s, last active %s. Ask them, or take it over with "+
 			"take-over saying why; the reason is noted on the issue. A worker who did nothing on it for %s may be "+
@@ -136,7 +139,10 @@ func workerFor(is *Issue, to, by, takeOver string, now time.Time, staleAfter tim
 func takeOverNote(o workOutcome, by, reason string, prev *Worker) string {
 	s := fmt.Sprintf("Taken over by %s from %s, who worked on it since %s and was last active %s", by, o.from,
 		prev.Since.Format(time.RFC3339), prev.Active.Format(time.RFC3339))
-	if o.wasStale {
+	switch {
+	case o.staleClaim:
+		s += " (a stale claim: nothing done on it past the bound, and no pull request open)"
+	case o.wasStale:
 		s += " (stale)"
 	}
 	if reason != "" {