TF-4068 Change profile (set identity as default) in setting

lib/features/manage_account/presentation/extensions/identity_extension.dart

@@ -1,4 +1,6 @@
+import 'package:jmap_dart_client/jmap/core/unsigned_int.dart';
 import 'package:jmap_dart_client/jmap/identities/identity.dart';
+import 'package:jmap_dart_client/jmap/mail/email/email_address.dart';
 import 'package:tmail_ui_user/features/manage_account/domain/model/identity_signature.dart';
 
 extension IdentityExtension on Identity {
@@ -16,4 +18,32 @@ extension IdentityExtension on Identity {
   IdentitySignature? toIdentitySignature() => id != null
       ? IdentitySignature(identityId: id!, signature: signatureAsString)
       : null;
+
+  Identity asDefault() => copyWith(sortOrder: UnsignedInt(0));
+
+  Identity copyWith({
+    IdentityId? id,
+    String? description,
+    String? name,
+    String? email,
+    Set<EmailAddress>? bcc,
+    Set<EmailAddress>? replyTo,
+    Signature? textSignature,
+    Signature? htmlSignature,
+    bool? mayDelete,
+    UnsignedInt? sortOrder,
+  }) {
+    return Identity(
+      id: id ?? this.id,
+      description: description ?? this.description,
+      name: name ?? this.name,
+      email: email ?? this.email,
+      bcc: bcc ?? this.bcc,
+      replyTo: replyTo ?? this.replyTo,
+      textSignature: textSignature ?? this.textSignature,
+      htmlSignature: htmlSignature ?? this.htmlSignature,
+      mayDelete: mayDelete ?? this.mayDelete,
+      sortOrder: sortOrder ?? this.sortOrder,
+    );
+  }
 }