docs: add plugin setup guide

plugin/lib/commonlibf4/include/RE/T/TESLoadGameEvent.h

@@ -0,0 +1,18 @@
+#pragma once
+
+#include "RE/B/BSTEvent.h"
+
+namespace RE
+{
+	class TESLoadGameEvent
+	{
+	public:
+		[[nodiscard]] static BSTEventSource<TESLoadGameEvent>* GetEventSource()
+		{
+			using func_t = decltype(&TESLoadGameEvent::GetEventSource);
+			static REL::Relocation<func_t> func{ ID::TESLoadGameEvent::GetEventSource };
+			return func();
+		}
+	};
+	static_assert(sizeof(TESLoadGameEvent) == 0x1);
+}