TF-527 Add presentation layer in add new identity

lib/features/identity_creator/presentation/model/identity_creator_arguments.dart

@@ -0,0 +1,14 @@
+
+import 'package:equatable/equatable.dart';
+import 'package:jmap_dart_client/jmap/account_id.dart';
+import 'package:model/model.dart';
+
+class IdentityCreatorArguments with EquatableMixin {
+  final AccountId accountId;
+  final UserProfile userProfile;
+
+  IdentityCreatorArguments(this.accountId, this.userProfile);
+
+  @override
+  List<Object?> get props => [accountId, userProfile];
+}

lib/features/identity_creator/presentation/model/signature_type.dart

@@ -0,0 +1,5 @@
+
+enum SignatureType {
+  plainText,
+  htmlTemplate
+}