v0.282.0: after_setup (the app's own sign-up switch), close sign-up now (decision 49), probes read lists + done_status (R-715)

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_0159rPz1ZhFKsS53msqPYxtS

controller/internal/stacks/setup_gate_test.go

@@ -162,14 +162,12 @@ func TestSetupGate_TheProbeOpensItOnlyWhenTheAppSaysSetUp(t *testing.T) {
 	dir := closedGate(t, m)
 	answer := `{"data":{"initialized":false}}`
 	var probeErr error
-	old := setupGateProbeGet
-	setupGateProbeGet = func(url string) ([]byte, error) {
+	t.Cleanup(SetSetupGateProbeGetForTest(func(url string) ([]byte, error) {
 		if url != "http://gapp:80/api/status" {
 			t.Errorf("probed %q", url)
 		}
 		return []byte(answer), probeErr
-	}
-	t.Cleanup(func() { setupGateProbeGet = old })
+	}))
 
 	m.SetupGateTick()
 	if c := LoadAppConfig(dir); !c.SetupGate.Closed() {