feat(copy): support legacy copy to clipboard for older browser (#581)

src/tools/roman-numeral-converter/roman-numeral-converter.vue

@@ -36,7 +36,7 @@ const validationRoman = useValidation({
 });
 
 const { copy: copyRoman } = useCopy({ source: outputRoman, text: 'Roman number copied to the clipboard' });
-const { copy: copyArabic } = useCopy({ source: outputNumeral, text: 'Arabic number copied to the clipboard' });
+const { copy: copyArabic } = useCopy({ source: () => String(outputNumeral), text: 'Arabic number copied to the clipboard' });
 </script>
 
 <template>