docs: add plugin setup guide

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

@@ -0,0 +1,14 @@
+#pragma once
+
+namespace RE
+{
+	class BSNavmeshTriangleEdgePortal
+	{
+	public:
+		// members
+		std::uint32_t otherMeshID;  // 0
+		std::uint16_t triangle;     // 4
+		std::int8_t   edgeIndex;    // 6
+	};
+	static_assert(sizeof(BSNavmeshTriangleEdgePortal) == 0x8);
+}