docs: add plugin setup guide

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

@@ -0,0 +1,13 @@
+#pragma once
+
+namespace RE
+{
+	class TOPIC_INFO_SCENEDATA
+	{
+	public:
+		// members
+		BGSScene*     scene;  // 00
+		std::uint32_t phase;  // 08
+	};
+	static_assert(sizeof(TOPIC_INFO_SCENEDATA) == 0x10);
+}