docs: add plugin setup guide

plugin/lib/commonlibf4/include/RE/H/hkStepInfo.h

@@ -0,0 +1,17 @@
+#pragma once
+
+#include "RE/H/hkPadSpu.h"
+
+namespace RE
+{
+	class hkStepInfo
+	{
+	public:
+		// members
+		hkPadSpu<float> m_startTime;     // 0x00
+		hkPadSpu<float> m_endTime;       // 0x04
+		hkPadSpu<float> m_deltaTime;     // 0x08
+		hkPadSpu<float> m_invDeltaTime;  // 0x0C
+	};
+	static_assert(sizeof(hkStepInfo) == 0x10);
+}