feat: REV-001 — DiceBear Notionists avatars on review cards

lib/features/reviews/widgets/review_card.dart

@@ -1,5 +1,6 @@
 // lib/features/reviews/widgets/review_card.dart
 import 'package:flutter/material.dart';
+import 'package:cached_network_image/cached_network_image.dart';
 import '../models/review_models.dart';
 import 'star_display.dart';
 
@@ -119,10 +120,22 @@ class _ReviewCardState extends State<ReviewCard> {
           // Header row
           Row(
             children: [
-              CircleAvatar(
-                radius: 18,
-                backgroundColor: _avatarColor(_review.username),
-                child: Text(initial, style: const TextStyle(color: Colors.white, fontWeight: FontWeight.bold, fontSize: 15)),
+              ClipOval(
+                child: CachedNetworkImage(
+                  imageUrl: 'https://api.dicebear.com/9.x/notionists/svg?seed=${Uri.encodeComponent(_review.username)}',
+                  width: 36,
+                  height: 36,
+                  placeholder: (_, __) => CircleAvatar(
+                    radius: 18,
+                    backgroundColor: _avatarColor(_review.username),
+                    child: Text(initial, style: const TextStyle(color: Colors.white, fontWeight: FontWeight.bold, fontSize: 15)),
+                  ),
+                  errorWidget: (_, __, ___) => CircleAvatar(
+                    radius: 18,
+                    backgroundColor: _avatarColor(_review.username),
+                    child: Text(initial, style: const TextStyle(color: Colors.white, fontWeight: FontWeight.bold, fontSize: 15)),
+                  ),
+                ),
               ),
               const SizedBox(width: 10),
               Expanded(