refactor user icon (#34)

Author: BenjaminCanape

lib/presentation/common/activity/widgets/activity_comments.dart

@@ -8,6 +8,7 @@ import '../../../../domain/entities/activity_comment.dart';
 import '../../../../core/utils/storage_utils.dart';
 import '../../../../domain/entities/user.dart';
 import '../../core/utils/color_utils.dart';
+import '../../core/utils/user_utils.dart';
 import '../view_model/activity_item_view_model.dart';
 import 'package:flutter_gen/gen_l10n/app_localizations.dart';
 
@@ -65,25 +66,13 @@ class ActivityComments extends HookConsumerWidget {
                 return pic != null
                     ? CircleAvatar(
                         radius: 50, backgroundImage: MemoryImage(pic))
-                    : Icon(
-                        Icons.person,
-                        size: 50,
-                        color: ColorUtils.black,
-                      );
+                    : UserUtils.personIcon;
               },
               loading: () {
-                return Icon(
-                  Icons.person,
-                  size: 50,
-                  color: ColorUtils.black,
-                );
+                return UserUtils.personIcon;
               },
               error: (error, stackTrace) {
-                return Icon(
-                  Icons.person,
-                  size: 50,
-                  color: ColorUtils.black,
-                );
+                return UserUtils.personIcon;
               },
             ),
           ),

lib/presentation/common/activity/widgets/activity_item.dart

@@ -192,23 +192,15 @@ class ActivityItem extends HookConsumerWidget {
                               profilePicture,
                               fit: BoxFit.cover,
                             )
-                          : Icon(
-                              Icons.person,
-                              size: 50,
-                              color: ColorUtils.black,
-                            ),
+                          : UserUtils.personIcon,
                     ),
                   );
                 },
                 loading: () {
                   return Center(child: UIUtils.loader);
                 },
                 error: (error, stackTrace) {
-                  return Icon(
-                    Icons.person,
-                    size: 50,
-                    color: ColorUtils.black,
-                  );
+                  return UserUtils.personIcon;
                 },
               ),
               const SizedBox(

lib/presentation/common/core/utils/user_utils.dart

@@ -3,9 +3,16 @@ import 'package:flutter/material.dart';
 import '../../../../domain/entities/user.dart';
 import '../../../../main.dart';
 import '../../user/screens/profile_screen.dart';
+import 'color_utils.dart';
 
 /// Utility class for user-related operations.
 class UserUtils {
+  static final personIcon = Icon(
+    Icons.person,
+    size: 50,
+    color: ColorUtils.black,
+  );
+
   /// Go to user profile
   static void goToProfile(User user) {
     navigatorKey.currentState?.push(