docs: add plugin setup guide

plugin/lib/commonlibf4/include/RE/S/SubGraphIdleRootData.h

@@ -0,0 +1,19 @@
+#pragma once
+
+#include "RE/B/BSFixedString.h"
+#include "RE/S/SubgraphIdentifier.h"
+
+namespace RE
+{
+	class SubGraphIdleRootData
+	{
+	public:
+		// members
+		SubgraphIdentifier subGraphID;      // 00
+		BSFixedString      idleRootName;    // 08
+		std::int8_t        count;           // 10
+		std::int8_t        activeCount;     // 11
+		bool               forFirstPerson;  // 12
+	};
+	static_assert(sizeof(SubGraphIdleRootData) == 0x18);
+}