Define UItemInstance base UObject with stable GUID

Source/NakedDesire/Items/ItemInstance.h

@@ -0,0 +1,22 @@
+#pragma once
+
+#include "CoreMinimal.h"
+#include "UObject/Object.h"
+#include "ItemInstance.generated.h"
+
+UCLASS(Abstract)
+class NAKEDDESIRE_API UItemInstance : public UObject
+{
+	GENERATED_BODY()
+	
+public:
+	virtual void PostInitProperties() override;
+	virtual void PostDuplicate(EDuplicateMode::Type DuplicateMode) override;
+
+	UFUNCTION(BlueprintPure, Category = "Item")
+	FGuid GetInstanceID() const { return InstanceID; }
+	
+private:
+	UPROPERTY(VisibleAnywhere, SaveGame, BlueprintReadOnly, Category = "Item", meta = (AllowPrivateAccess = "true"))
+	FGuid InstanceID;
+};