https://github.com/BYVoid/OpenCC/pull/894
Fix missing cstdint for GCC 15

--- a/src/SerializedValues.cpp
+++ b/src/SerializedValues.cpp
@@ -17,6 +17,7 @@
  */
 
 #include <cassert>
+#include <cstdint>
 #include <cstring>
 
 #include "Lexicon.hpp"