docs: add plugin setup guide

plugin/lib/commonlibf4/include/RE/P/PACKAGE_DATA.h

@@ -0,0 +1,17 @@
+#pragma once
+
+namespace RE
+{
+	class PACKAGE_DATA
+	{
+	public:
+		// members
+		std::uint32_t packFlags;              // 0
+		std::int8_t   packType;               // 4
+		std::int8_t   interruptOverrideType;  // 5
+		std::int8_t   maxSpeed;               // 6
+		std::uint16_t foBehaviorFlags;        // 8
+		std::uint16_t packageSpecificFlags;   // A
+	};
+	static_assert(sizeof(PACKAGE_DATA) == 0xC);
+}