layer1: add namespace manager summary

pkg/utils/namespace_manager_model_test.go

@@ -154,3 +154,10 @@ func TestNamespaceRemovalStrategyValues(t *testing.T) {
 		t.Fatalf("unexpected dispatch-remove strategy value")
 	}
 }
+
+func TestNamespaceManagerSummaryZeroValue(t *testing.T) {
+	summary := NamespaceManagerSummary{}
+	if summary.TotalNamespaces != 0 {
+		t.Fatalf("expected zero total namespaces")
+	}
+}