docs(arch): add documentation

packages/wyatt_architecture/example/lib/data/repositories/photo_repository_impl.dart

@@ -36,7 +36,7 @@ class PhotoRepositoryImpl extends PhotoRepository {
   @override
   FutureOrResult<void> addPhotoToFavorites(Photo photo) => Result.tryCatchAsync(
         () => _favoriteLocalDataSource.addPhotoToFavorites(photo),
-        (error) => ClientException('Cannot add photo to favorites.'),
+        (error) => const ClientException('Cannot add photo to favorites.'),
       );
 
   @override
@@ -63,14 +63,14 @@ class PhotoRepositoryImpl extends PhotoRepository {
   FutureOrResult<List<Album>> getAllAlbums({int? start, int? limit}) =>
       Result.tryCatchAsync(
         () => _albumRemoteDataSource.getAllAlbums(start: start, limit: limit),
-        (error) => ServerException('Cannot retrieve all albums.'),
+        (error) => const ServerException('Cannot retrieve all albums.'),
       );
 
   @override
   FutureOrResult<List<Photo>> getAllPhotos({int? start, int? limit}) async =>
       Result.tryCatchAsync(
         () => _photoRemoteDataSource.getAllPhotos(start: start, limit: limit),
-        (error) => ServerException('Cannot retrieve all photos.'),
+        (error) => const ServerException('Cannot retrieve all photos.'),
       );
 
   @override
@@ -88,7 +88,7 @@ class PhotoRepositoryImpl extends PhotoRepository {
       }
       return Ok(response);
     } catch (_) {
-      return Err(
+      return const Err(
         ClientException('Cannot retrieve all photos from favorites.'),
       );
     }