fix fields reactivity in export drawer (#14695)

app/src/views/private/components/export-sidebar-detail.vue

@@ -281,6 +281,15 @@ const exportSettings = reactive({
 	sort: `${primaryKeyField.value?.field ?? ''}`,
 });
 
+watch(
+	fields,
+	() => {
+		if (props.layoutQuery?.fields) return;
+		exportSettings.fields = fields.value?.map((field) => field.field);
+	},
+	{ immediate: true }
+);
+
 watch(
 	() => props.layoutQuery,
 	() => {