Add styling for last update text: adjust font size, color, and text shadow for better visibility

web/client/src/App.css

@@ -181,6 +181,13 @@ body {
   50% { opacity: 0.3; }
 }
 
+.last-update-text {
+  font-size: 0.65rem;
+  color: var(--mc-text-gray, #aaa);
+  text-shadow: 1px 1px 0 var(--mc-dark);
+  white-space: nowrap;
+}
+
 /* === Command Toast === */
 .command-toast {
   position: fixed;