refactor: declare format timestamp as variable for consistency

webroot/js/components/chat/message.js

@@ -16,6 +16,7 @@ export default class Message extends Component {
       const { image, author, body, timestamp } = message;
       const formattedMessage = formatMessageText(body, username);
       const avatar = image || generateAvatar(author);
+      const formattedTimestamp = formatTimestamp(timestamp);
 
       const authorColor = messageBubbleColorForString(author);
       const avatarBgColor = { backgroundColor: authorColor };
@@ -35,7 +36,7 @@ export default class Message extends Component {
               </div>
               <div
                 class="message-text text-gray-300 font-normal overflow-y-hidden"
-                title=${`Sent at ${formatTimestamp(timestamp)}`}
+                title=${formattedTimestamp}
                 dangerouslySetInnerHTML=${
                   { __html: formattedMessage }
                 }

webroot/js/utils/chat.js

@@ -284,9 +284,9 @@ export function formatTimestamp(sentAt) {
 
   let diffInDays = ((new Date()) - sentAt) / (24 * 3600 * 1000);
   if (diffInDays >= 1) {
-    return `${sentAt.toLocaleDateString('en-US', {dateStyle: 'medium'})} at ` +
+    return `Sent at ${sentAt.toLocaleDateString('en-US', {dateStyle: 'medium'})} at ` +
       sentAt.toLocaleTimeString();
   }
 
-  return sentAt.toLocaleTimeString();
+  return `Sent at ${sentAt.toLocaleTimeString()}`;
 }