fix(frontend/pageMetadata): ページタイトルが更新されない問題 (#13289)

Co-authored-by: syuilo <Syuilotan@yahoo.co.jp>
Co-authored-by: syuilo <4439005+syuilo@users.noreply.github.com>

packages/frontend/src/pages/role.vue

@@ -93,10 +93,10 @@ const headerTabs = computed(() => [{
 	title: i18n.ts.timeline,
 }]);
 
-definePageMetadata(computed(() => ({
-	title: role.value?.name,
+definePageMetadata(() => ({
+	title: role.value ? role.value.name : i18n.ts.role,
 	icon: 'ti ti-badge',
-})));
+}));
 </script>
 
 <style lang="scss" module>