Clean up events, add weapon tag for weaker on swing

Zennysoft.Game.Ma/src/map/UnlockableDoor.cs

@@ -11,13 +11,18 @@ public partial class UnlockableDoor : Node3D, IDoor
 
   public void OnReady()
   {
-	UnlockArea.AreaEntered += UnlockArea_AreaEntered;
+    UnlockArea.AreaEntered += UnlockArea_AreaEntered;
   }
 
   private void UnlockArea_AreaEntered(Area3D area)
   {
-	var children = GetChildren();
-	foreach (var child in children)
-	  child.QueueFree();
+    var children = GetChildren();
+    foreach (var child in children)
+      child.QueueFree();
+  }
+
+  public void OnExitTree()
+  {
+    UnlockArea.AreaEntered -= UnlockArea_AreaEntered;
   }
 }