format dart files

formats all dart files using `dart format .` from the root project dir

this makes the code style repeatable by new contributors and makes PR review easier

lib/widgets/unread_badge.dart

@@ -3,10 +3,7 @@ import 'package:flutter/material.dart';
 class UnreadBadge extends StatelessWidget {
   final int count;
 
-  const UnreadBadge({
-    super.key,
-    required this.count,
-  });
+  const UnreadBadge({super.key, required this.count});
 
   @override
   Widget build(BuildContext context) {