Refactor some R_ext includes

Author: Enchufa2

ChangeLog

@@ -1,3 +1,9 @@
+2025-12-04  Iñaki Ucar <[email protected]>
+
+	* inst/include/Rcpp/r/headers.h: Include <R_ext/Visibility.h>
+	* inst/include/RcppCommon.h: Drop <R_ext/Callbacks.h>, not used anymore
+	and dropped from the API; drop <R_ext/Visibility.h>, included above
+
 2025-12-03  Dirk Eddelbuettel  <[email protected]>
 
 	* DESCRIPTION (Version, Date): Roll micro version and date

inst/include/Rcpp/r/headers.h

@@ -72,6 +72,7 @@
 #include <R_ext/Complex.h>
 #include <R_ext/Parse.h>
 #include <R_ext/Rdynload.h>
+#include <R_ext/Visibility.h>
 #include <Rversion.h>
 
 /* Ensure NORET defined (normally provided by R headers with R >= 3.2.0) */

inst/include/RcppCommon.h

@@ -73,8 +73,6 @@ namespace Rcpp {
 #include <typeinfo>
 #include <utility>
 #include <Rcpp/sprintf.h>
-#include <R_ext/Callbacks.h>
-#include <R_ext/Visibility.h>
 #include <Rcpp/utils/tinyformat.h>
 
 #include <Rmath.h>