feat(ui): use branded placeholders for images and profile avatars

lib/core/constants/app_assets.dart

@@ -29,6 +29,8 @@ abstract final class AppAssets {
   static const imageFigure = 'figure';
   static const imageLine = 'line';
   static const imageLineVariant = 'line_variant';
+  static const imagePlaceholder = 'assets/images/image_placeholder.png';
+  static const avatarPlaceholder = 'assets/images/avatar_placeholder.png';
 
   // Legal documents.
   static const legalPrivacyPolicy = 'assets/legal/privacy_policy.txt';

lib/features/profile/presentation/widgets/edit_profile_dialog.dart

@@ -11,14 +11,14 @@ import '../../../../../uikit/buttons/button_state.dart';
 import '../../../../../uikit/buttons/main_button.dart';
 import '../../../../../uikit/buttons/secondary_button.dart';
 import '../../../../../uikit/dialogs/app_feedback_dialog.dart';
-import '../../../../../uikit/images/network_image_widget.dart';
 import '../../../../../uikit/themes/colors/app_color_theme.dart';
 import '../../../../../uikit/themes/text/app_text_theme.dart';
 import '../../../auth/domain/entities/user.dart';
 import '../../../auth/presentation/validators/auth_validators.dart';
 import '../../../auth/presentation/widgets/auth_text_field.dart';
 import '../../domain/repositories/profile_repository.dart';
 import '../cubits/update_profile_cubit.dart';
+import 'profile_avatar_image.dart';
 import 'profile_dialog_shell.dart';
 
 /// Opens the edit-profile dialog and returns the refreshed user on success.
@@ -251,7 +251,7 @@ final class _AvatarPreview extends StatelessWidget {
         fit: BoxFit.cover,
       );
     }
-    return NetworkImageWidget(
+    return ProfileAvatarImage(
       imageUrl: imageUrl ?? '',
       height: 296,
     );

lib/features/profile/presentation/widgets/profile_avatar_image.dart

@@ -0,0 +1,76 @@
+import 'package:cached_network_image/cached_network_image.dart';
+import 'package:flutter/material.dart';
+
+import '../../../../../core/constants/app_assets.dart';
+
+/// Profile-local network image widget with avatar-specific fallback artwork.
+class ProfileAvatarImage extends StatelessWidget {
+  /// Remote image URL.
+  final String imageUrl;
+
+  /// Height.
+  final double height;
+
+  /// Optional width.
+  final double? width;
+
+  /// Fit.
+  final BoxFit fit;
+
+  /// Creates an instance of [ProfileAvatarImage].
+  const ProfileAvatarImage({
+    required this.imageUrl,
+    required this.height,
+    this.width,
+    this.fit = BoxFit.cover,
+    super.key,
+  });
+
+  @override
+  Widget build(BuildContext context) {
+    return CachedNetworkImage(
+      imageUrl: imageUrl,
+      height: height,
+      width: width,
+      fit: fit,
+      placeholder: (_, _) => _ProfileAvatarPlaceholder(
+        height: height,
+        width: width,
+        fit: fit,
+      ),
+      errorWidget: (_, _, _) => _ProfileAvatarPlaceholder(
+        height: height,
+        width: width,
+        fit: fit,
+      ),
+    );
+  }
+}
+
+final class _ProfileAvatarPlaceholder extends StatelessWidget {
+  final double height;
+  final double? width;
+  final BoxFit fit;
+
+  const _ProfileAvatarPlaceholder({
+    required this.height,
+    required this.width,
+    required this.fit,
+  });
+
+  @override
+  Widget build(BuildContext context) {
+    return Image.asset(
+      AppAssets.avatarPlaceholder,
+      height: height,
+      width: width,
+      fit: fit,
+      errorBuilder: (_, _, _) => const Center(
+        child: Icon(
+          Icons.image_not_supported_outlined,
+          size: 32,
+        ),
+      ),
+    );
+  }
+}

lib/features/profile/presentation/widgets/user_section_widget.dart

@@ -4,10 +4,10 @@ import '../../../../../core/constants/app_strings.dart';
 import '../../../../../uikit/buttons/main_button.dart';
 import '../../../../../uikit/buttons/secondary_button.dart';
 import '../../../../../uikit/cards/app_card.dart';
-import '../../../../../uikit/images/network_image_widget.dart';
 import '../../../../../uikit/themes/colors/app_color_theme.dart';
 import '../../../../../uikit/themes/text/app_text_theme.dart';
 import '../../../auth/domain/entities/user.dart';
+import 'profile_avatar_image.dart';
 
 /// The first profile section with the basic authenticated user data.
 class UserSectionWidget extends StatelessWidget {
@@ -42,7 +42,7 @@ class UserSectionWidget extends StatelessWidget {
             child: ClipOval(
               child: SizedBox.square(
                 dimension: 140,
-                child: NetworkImageWidget(
+                child: ProfileAvatarImage(
                   imageUrl: user.avatar ?? '',
                   height: 140,
                 ),

lib/uikit/images/network_image_widget.dart

@@ -1,7 +1,7 @@
 import 'package:cached_network_image/cached_network_image.dart';
 import 'package:flutter/material.dart';
 
-import '../themes/colors/app_color_theme.dart';
+import '../../core/constants/app_assets.dart';
 
 /// Widget for displaying cached network images.
 class NetworkImageWidget extends StatelessWidget {
@@ -26,26 +26,24 @@ class NetworkImageWidget extends StatelessWidget {
         imageUrl: imageUrl,
         fit: BoxFit.cover,
         placeholder: (_, _) => const _ImagePlaceholder(),
-        errorWidget: (_, _, _) => const _ImagePlaceholder(
-          icon: Icons.image_not_supported_outlined,
-        ),
+        errorWidget: (_, _, _) => const _ImagePlaceholder(),
       ),
     );
   }
 }
 
 class _ImagePlaceholder extends StatelessWidget {
-  final IconData icon;
-  const _ImagePlaceholder({this.icon = Icons.image_outlined});
+  const _ImagePlaceholder();
 
   @override
   Widget build(BuildContext context) {
-    return SizedBox(
-      child: Center(
+    return Image.asset(
+      AppAssets.imagePlaceholder,
+      fit: BoxFit.cover,
+      errorBuilder: (_, _, _) => const Center(
         child: Icon(
-          icon,
+          Icons.image_not_supported_outlined,
           size: 64,
-          color: AppColorTheme.of(context).disabled,
         ),
       ),
     );