Advise a recheck for an unanswered check on a ready or rejected delivery (issue 451)

That check answered once, so the build queue is the wrong place to look.
mesh-delivery names the delivery's state as data (held); the controller
reads it and never the words. A line without it keeps the advice of 438.

cmd/mesh-controller/plain_words.go

@@ -885,6 +885,11 @@ func stalledWords(l stalledLine, o conditions.Observation) (headline, explanatio
 // within its bound (novox/hq issue 438): mesh-delivery holds no delivery of it, so there is nothing to stop, release
 // or close, and no action is offered. The operator's acts are a new commit, which asks the check again, or a look
 // at the build queue, where a check that never ran may still wait.
+//
+// A head whose delivery is held in ready or rejected is said the same way (novox/hq issue 441), and mesh-delivery
+// names that state as data (Held). Its check answered once, so the build queue is the wrong place to look: the step
+// is a recheck of the delivery, named by its id, which asks the check again (novox/hq issue 451). It is advised, not
+// offered as an action, since the controller is not granted the recheck.
 func unansweredWords(l stalledLine, o conditions.Observation) (headline, explanation, resolved, needs string,
 	actions []conditions.Action) {
 	repository, _, _ := strings.Cut(l.ID, "@")
@@ -899,13 +904,23 @@ func unansweredWords(l stalledLine, o conditions.Observation) (headline, explana
 	if d, err := time.ParseDuration(l.Bound); err == nil {
 		limit = ", past its limit of " + humanDuration(d)
 	}
-	which := "Its merge check"
+	check := "merge check"
 	if said := uncheckedWaitWords(l); len(said) > 0 {
-		which = "Its merge check (" + strings.Join(said, ", ") + ")"
+		check = "merge check (" + strings.Join(said, ", ") + ")"
 	}
-	if o.Resolver == conditions.ResolverOperator {
-		needs = "push a new commit to its branch, which asks the check again, or see whether its check still waits " +
-			"in the build queue: mesh-controller.queue."
+	which := "Its " + check
+	switch l.Held {
+	case "ready", "rejected":
+		which = "Its delivery is " + l.Held + ", but on the forge its " + check
+		if o.Resolver == conditions.ResolverOperator {
+			needs = "recheck its delivery, which asks its check again — mesh-delivery.recheck with id " + l.ID +
+				" and why — or push a new commit to its branch, " + FromMeshMCPServer
+		}
+	default:
+		if o.Resolver == conditions.ResolverOperator {
+			needs = "push a new commit to its branch, which asks the check again, or see whether its check still " +
+				"waits in the build queue: mesh-controller.queue."
+		}
 	}
 	return fmt.Sprintf("%s's merge check has not answered %s", pull, long),
 		fmt.Sprintf("%s is open on a branch that requires the merge check. %s was asked and has not answered %s%s. "+