Name the hold a waiting walk waits on in plans (issue 529)

A walk whose delivery was held for a person said only that it waits for
mesh-delivery's word and that plans go starts it by hand, pointing the
reader at a hand start instead of the person's decision. Ask mesh-delivery
what holds each waiting walk and say the held delivery, its reason and
mesh-delivery.release, or the delivery not at its turn.

cmd/mesh-controller/delivery.go

@@ -82,6 +82,29 @@ func waitingNote(p inventory.Plan) string {
 		p.Delivery.Awaits, p.ID)
 }
 
+// waitingSaid is what a walk waiting for its word says when the delivery's owner said what holds it (novox/hq
+// issue 529): a delivery held for a person, its reason and the verb that releases it — the person's decision, not
+// a hand start — or the deliveries not at their turn. Told nothing, it is waitingNote.
+func waitingSaid(p inventory.Plan, lines []stalledLine) string {
+	if len(lines) == 0 {
+		return waitingNote(p)
+	}
+	var held, other []string
+	for _, l := range lines {
+		if l.State == "held" {
+			held = append(held, l.Says)
+		} else {
+			other = append(other, l.Says)
+		}
+	}
+	if len(held) > 0 {
+		return fmt.Sprintf("published; its walk waits for %s's word, and a delivery it carries is held for a person: %s",
+			p.Delivery.Awaits, strings.Join(held, "; "))
+	}
+	return fmt.Sprintf("published; its walk waits for %s's word: %s — `plans go %s --why …` starts it by hand",
+		p.Delivery.Awaits, strings.Join(other, "; "), p.ID)
+}
+
 // letGo gives a waiting walk its word: by the delivery's owner, or a person. The next advance asks its
 // first tier. Refused for a walk that does not wait.
 func letGo(ctx context.Context, inv *inventory.Inventory, id, by, why string) (inventory.Plan, error) {