remove the cloned attachnode when detaching a part

KSPCommunityFixes/BugFixes/ReRootCloneSurfaceAttach.cs

@@ -1,4 +1,5 @@
-using HarmonyLib;
+using Expansions.Missions.Editor;
+using HarmonyLib;
 using System;
 using System.Collections.Generic;
 using System.Linq;
@@ -31,6 +32,11 @@ protected override void ApplyPatches(List<PatchInfo> patches)
                 PatchMethodType.Postfix,
                 AccessTools.Method(typeof(Part), nameof(Part.FindAttachNode)),
                 this));
+
+            patches.Add(new PatchInfo(
+                PatchMethodType.Postfix,
+                AccessTools.Method(typeof(EditorLogicBase), nameof(EditorLogicBase.clearAttachNodes)),
+                this));
         }
 
         // In stock, this function is called after reversing a surface attachment during a re-root operation.
@@ -81,5 +87,20 @@ static void Part_FindAttachNode_Postfix(Part __instance, string nodeId, ref Atta
                 __result = newSrfAttachNode;
             }
         }
+
+        // In the editor, when detaching parts, remove the extra attachnode we added
+        static void EditorLogicBase_clearAttachNodes_Postfix(Part part)
+        {
+            for (int i = 0; i < part.attachNodes.Count; i++)
+            {
+                AttachNode attachNode = part.attachNodes[i];
+
+                if (attachNode.id == CLONED_NODE_ID && attachNode.attachedPart.IsNullRef())
+                {
+                    part.attachNodes.RemoveAt(i);
+                    return;
+                }
+            }
+        }
     }
 }