feat: use red offline icon for subplebbits that are most likely offline (ipns record fails to update)

src/hooks/use-is-subplebbit-offline.ts

@@ -0,0 +1,19 @@
+import { useTranslation } from 'react-i18next';
+import { Subplebbit } from '@plebbit/plebbit-react-hooks';
+import { getFormattedTimeAgo } from '../lib/utils/time-utils';
+
+const useIsSubplebbitOffline = (subplebbit: Subplebbit) => {
+  const { t } = useTranslation();
+  const { updatedAt, updatingState } = subplebbit || {};
+  const isProbablyOffline = !updatedAt || (updatedAt && updatedAt < Date.now() / 1000 - 60 * 60);
+  const isDefinitelyOffline = updatingState === 'failed';
+  const isOffline = isProbablyOffline || isDefinitelyOffline;
+
+  const offlineTitle = updatedAt
+    ? isOffline && t('posts_last_synced_info', { time: getFormattedTimeAgo(updatedAt), interpolation: { escapeValue: false } })
+    : t('subplebbit_offline_info');
+
+  return { isOffline, isDefinitelyOffline, offlineTitle };
+};
+
+export default useIsSubplebbitOffline;