feat(account): display source logos in followed sources list

- Replace default source icon with network image for source logos
- Add error handling to fall back to default icon if image loading fails
- Implement sizing and clipping for consistent logo appearance

Author: fulleni

lib/account/view/followed_contents/sources/followed_sources_list_page.dart

@@ -72,7 +72,19 @@ class FollowedSourcesListPage extends StatelessWidget {
             itemBuilder: (context, index) {
               final source = followedSources[index];
               return ListTile(
-                leading: const Icon(Icons.source_outlined),
+                leading: SizedBox(
+                  width: 40,
+                  height: 40,
+                  child: ClipRRect(
+                    borderRadius: BorderRadius.circular(AppSpacing.sm),
+                    child: Image.network(
+                      source.logoUrl,
+                      fit: BoxFit.cover,
+                      errorBuilder: (context, error, stackTrace) =>
+                          const Icon(Icons.source_outlined),
+                    ),
+                  ),
+                ),
                 title: Text(source.name),
                 subtitle: Text(
                   source.description,