fix

void Adventure::AddPlayer(std::string character_name, bool add_client_to_instance)
{
    if(!PlayerExists(character_name))
    {
        int client_id = database.GetCharacterID(character_name.c_str());
        if(add_client_to_instance && client_id)
        {
            database.AddClientToInstance(instance_id, client_id);
        }

        if (client_id)
            players.push_back(character_name);
    }
}