feat: add initial People Playground mod development kit

extracted_wiki_content/internalReference/actondestroy.txt

@@ -0,0 +1,14 @@
+URL: https://wiki.studiominus.nl/internalReference/ActOnDestroy.html
+Title: People Playground Modding - ActOnDestroy
+==================================================
+
+public class ActOnDestroy
+Inherits MonoBehaviour
+Behaviour that invokes an event when it is destroyed
+Fields
+public UnityEvent Event
+The event that is invoked when the behaviour is destroyed
+
+public GameObject[] DestroyWith
+[SkipSerialisation]
+An array of other objects that will be destroyed when this behaviour is destroyed