Say a pull request nobody checks as a delivery held, owned by mesh-delivery (hq issue 347)

The confirmation review asked for the delivery domain's own vocabulary
instead of a provider standing. A gitea health check would need a `tools`
list (turning gitea's tools into seat verbs), a check of another kind
beside it, and would hold the forge's own deliveries at the first-node
gate; so the delivery's owner says it, with the word it already has.

- gitea_open_pulls (gitea): every open pull request from the forge itself,
  with what its base requires and the statuses its head has.
- mesh-delivery asks it every five minutes and keeps its own first-seen
  time per head (the forge's update time moves on every comment). A head
  on a base requiring mesh/merge-gate OR mesh/repo-check (hq requires only
  the second) with neither for ten minutes is a `stalled` line in state
  `unannounced`, which the controller raises as delivery.<id>.stalled (D14);
  H2 has nothing to close. Once announced it is a delivery of its own.
- The gitea-side watcher and its provider standing are gone.

modules/mesh-delivery/cmd/mesh-delivery/main.go

@@ -68,7 +68,7 @@ func run(h *Holder, l *listening) {
 	go func() {
 		tick := time.NewTicker(10 * time.Second)
 		defer tick.Stop()
-		last := time.Now()
+		last, looked := time.Now(), time.Time{}
 		for now := range tick.C {
 			if now.Sub(last) >= 30*time.Second {
 				last = now
@@ -76,6 +76,11 @@ func run(h *Holder, l *listening) {
 					logf("[mesh-delivery] the controller's walks cannot be read: %v", err)
 				}
 			}
+			// Every open pull request, from the forge itself, every five minutes (novox/hq issue 347).
+			if now.Sub(looked) >= 5*time.Minute {
+				looked = now
+				h.SeeOpenPulls()
+			}
 			h.Tick()
 			h.Flush()
 		}