refactor: include a missing <limits> header in fs.cpp

... needed for std::numeric_limits<T>::max on WIN32

Author: joankaradimov

src/fs.cpp

@@ -16,6 +16,7 @@
 #define NOMINMAX
 #endif
 #include <codecvt>
+#include <limits>
 #include <windows.h>
 #endif