docs: add plugin setup guide

plugin/lib/commonlibf4/include/RE/B/BGSFeaturedItemMessage.h

@@ -0,0 +1,18 @@
+#pragma once
+
+#include "RE/B/BaseFormComponent.h"
+
+namespace RE
+{
+	class __declspec(novtable) BGSFeaturedItemMessage :
+		public BaseFormComponent  // 00
+	{
+	public:
+		static constexpr auto RTTI{ RTTI::BGSFeaturedItemMessage };
+		static constexpr auto VTABLE{ VTABLE::BGSFeaturedItemMessage };
+
+		// members
+		BGSMessage* featuredItemMessage;  // 08
+	};
+	static_assert(sizeof(BGSFeaturedItemMessage) == 0x10);
+}