style(frontend): apply ultracite 7.12 formatting and lint rules

frontend/src/lib/format/peer.ts

@@ -38,7 +38,7 @@ export function initials(name: string): string {
   if (words.length === 0) {
     return "?";
   }
-  const first = words[0][0];
+  const first = words[0].charAt(0);
   if (words.length === 1) {
     return first.toUpperCase();
   }