// AddTagTo <albumName> <tag>
public string Execute(params string[] data)
{
var albumName = data[0];
var tagName = data[1];
if (Session.User is null || !tagService.IsOwner(albumName, Session.User))
{
throw new ArgumentException("Invalid credentials!");
}
tagService.AddTagTo(albumName, tagName);
return($"Tag {tagName} added to {albumName}");
}