rename: IUP 库目录重命名为 libs/IUP

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

libs/IUP/include/iupluatuio.h

@@ -0,0 +1,20 @@
+/** \file
+ * \brief Binding of iuptuio to Lua.
+ *
+ * See Copyright Notice in "iup.h"
+ */
+ 
+#ifndef __IUPLUATUIO_H 
+#define __IUPLUATUIO_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+int iuptuiolua_open (lua_State * L);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif