Root nodes join through ModRoot.AddDeferred, so a reload that unloads the mod first never hands Godot a freed node

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/DialogModInitializer.cs

@@ -57,7 +57,7 @@ namespace Cthangover.Mods.Dialog
 
             // Deferred: OnModResourcesReady fires while the root is still
             // setting up autoload children, so a direct AddChild is rejected.
-            root.CallDeferred("add_child", new DialogScriptRunner { Name = "DialogRunner" });
+            ModRoot.AddDeferred(new DialogScriptRunner { Name = "DialogRunner" });
         }
     }
 }

test_suites/autoplay/src/TestRunnerInitializer.cs

@@ -63,7 +63,7 @@ namespace Mods.TestRunner
             // Deferred: сцена ещё строится; драйвер внутри сам выдерживает
             // стартовую паузу и лениво ищет DialogBox, поэтому порядок с
             // загрузкой сцены не важен.
-            root.CallDeferred("add_child", new DialogAutoDriverNode(choices, timeout, dialogs));
+            ModRoot.AddDeferred(new DialogAutoDriverNode(choices, timeout, dialogs));
         }
 
         private static List<int> ParseChoices(string[] args)

test_suites/gdscript/src/GdscriptTest.cs

@@ -24,7 +24,7 @@ namespace Mods.DialogBase.Tests
                 return;
             queued = true;
             GameLogger.Log("TEST", "GdscriptTest: activating");
-            (Godot.Engine.GetMainLoop() as SceneTree)?.Root?.CallDeferred("add_child", new GdscriptTestDriverNode());
+            ModRoot.AddDeferred(new GdscriptTestDriverNode());
         }
     }