Manually remove the wrappers from _constants.hpp that are guaranteed
to break the build, force the rest into cppgir.ignore

--- cmake/external/glib/generate_cppgir.cmake.orig	Mon Mar  2 18:46:48 2026
+++ cmake/external/glib/generate_cppgir.cmake	Tue Aug  4 23:00:08 2026
@@ -35,6 +35,11 @@
         ${gen_dst}
         ${gir}
     COMMAND
+	sh
+	${CMAKE_SOURCE_DIR}/cppgir_clean.sh
+	${gen_dst}
+	${CMAKE_SOURCE_DIR}
+    COMMAND
         echo 1> ${gen_timestamp}
     COMMENT "Generating C++ wrapper for ${gir} (${target_name})"
     DEPENDS
