docs: add plugin setup guide

plugin/lib/commonlibf4/include/RE/A/ActorItemEquipped.h

@@ -0,0 +1,16 @@
+#pragma once
+
+namespace RE
+{
+	namespace ActorItemEquipped
+	{
+		class Event
+		{
+		public:
+			// members
+			const TESBoundObject* item;      // 00
+			const Actor*          equipper;  // 08
+		};
+		static_assert(sizeof(Event) == 0x10);
+	}
+}