feat: add initial People Playground mod development kit

extracted_wiki_content/internalReference/messages_idamage.txt

@@ -0,0 +1,10 @@
+URL: https://wiki.studiominus.nl/internalReference/Messages_IDamage.html
+Title: People Playground Modding - Messages.IDamage
+==================================================
+
+public interface IDamage
+This nested type resides in Messages
+Implements a receiver for the "Damage" message. It's invoked when something tries to damage the object (think energy weapons and such).Passes the relevant amount of damage.
+Methods
+void Damage(float damage)
+No description provided