add set media fields

backend/tests/Fakes/FakeSetRepository.php

@@ -19,6 +19,8 @@ class FakeSetRepository implements SetRepository
         $set = new DomainSet(
             id: $id,
             name: $dto->name,
+            description: $dto->description,
+            iconImageUrl: $dto->iconImageUrl,
         );
         $this->setsById[$id] = $set;
 
@@ -52,6 +54,8 @@ class FakeSetRepository implements SetRepository
         return new DomainSet(
             id: $set->getId(),
             name: $set->getName(),
+            description: $set->getDescription(),
+            iconImageUrl: $set->getIconImageUrl(),
         );
     }
 }