Keep the first-machine gate behind a switch for walks begun before hq ADR 0360, and test both paths

cmd/mesh-controller/issue648_test.go

@@ -20,8 +20,8 @@ func TestANoMoveTierWaitsForNoNewReport(t *testing.T) {
 	ctx := t.Context()
 	inv := g.open.inventory
 
-	// app is the build machine, so a module of the next tier is built by it: the tier gates the next on app
-	// running on its machines.
+	// app holds the build seat, so a module of the next tier is built by it; since novox/hq ADR 0360 §3 that gates
+	// nothing.
 	for _, m := range []catalogue.Manifest{
 		{Module: "app", Version: "c2", Claims: []catalogue.Claim{{Name: "node-build-agent", Scope: catalogue.ScopeNode}}},
 		{Module: "web", Version: "w1"},
@@ -71,7 +71,8 @@ func TestANoMoveTierWaitsForNoNewReport(t *testing.T) {
 		t.Fatalf("the walk waits on a no-move tier for a report nothing will cause: tier %d, %s %q", p.Tier, p.State, p.Note)
 	}
 
-	// A machine that has not answered its last send is still waited on: no move is not "never sent".
+	// A machine that has not answered its last send is not waited on either: a built-by edge gates no tier
+	// (novox/hq ADR 0360 §3). Before, the walk waited for app on laptop.
 	p.Tier, p.State, p.Note = 0, inventory.PlanRolling, ""
 	if err := inv.RecordSent(ctx, nodeID(t, g.open, "laptop"), "d-laptop-later", map[string]string{"app": "c1"}); err != nil {
 		t.Fatal(err)
@@ -81,7 +82,7 @@ func TestANoMoveTierWaitsForNoNewReport(t *testing.T) {
 	}
 	advancePlans(ctx, g.open)
 	p = g.plan(t)
-	if p.Tier != 0 || !strings.Contains(p.Note, "waiting for app on laptop") {
-		t.Fatalf("a machine that has not answered its last send was not waited on: tier %d, %q", p.Tier, p.Note)
+	if p.Tier < 1 || strings.Contains(p.Note, "waiting for app") {
+		t.Fatalf("the walk waits on a built-by edge: tier %d, %q", p.Tier, p.Note)
 	}
 }