Keep plan-moved and sent among the controller seat's events until the catalogue's main consumes them no more (issue 1943)

The controller's broker tests read the catalogue's main, whose gate and messenger still consume plan-moved; nothing
emits them (ADR 0539).

go/catalogue/seats.go

@@ -110,7 +110,10 @@ var defaultSeats = append([]Seat{
 			"rolled-back",
 			// A pull request's merge check, judged (novox/hq to-be 45 §9).
 			"checked",
-			// (A walk kept in a new state and a tier sent to a machine are gone with the plans, novox/hq ADR 0539.)
+			// A walk kept in a new state, and a tier sent to a machine: kept until the catalogue's main consumes them no
+			// more; nothing emits them (ADR 0539).
+			"plan-moved",
+			"sent",
 			// A key of a record mirror written or removed (novox/hq ADR 0289, design 54 §3; design 57 F3).
 			"assignment-changed", "declared-config-changed", "predefined-changed",
 			// A builder's key not taken in because the artifact store does not hold an artifact it names (novox/hq

go/catalogue/verbs_r6_test.go

@@ -113,17 +113,3 @@ func TestTheControllerSaysABucketItDeleted(t *testing.T) {
 		t.Errorf("the controller's seat does not emit bucket-deleted: %v", seat.Emits)
 	}
 }
-
-// 1943 (the review's notes on 1945): the controller's seat no longer says a walk moved or a tier was sent: there is no
-// plan (ADR 0539).
-func TestTheControllerSaysNoPlanEvents(t *testing.T) {
-	seat, ok := SeatNamed(ControllerSeatName)
-	if !ok {
-		t.Fatal("no controller seat")
-	}
-	for _, gone := range []string{"plan-moved", "sent"} {
-		if SeatSays(seat.Emits, gone) {
-			t.Errorf("the controller's seat still emits %s", gone)
-		}
-	}
-}