i am trying use calendso in dev mode to see if i can more fucntionality , i am using react-draft-WYSIWYG to come up with a rich text editor, which i have achieved. now to it i would like to add some functionalities like below: while a user enters text, i want to enable them enter a dynamic variable that will change in the final text. (assuming this entered text will be an email reminder sent to several recipients,) i want it that a user can enter a variable like @name and this will be translated into the name of the recipient receiving that email. I am getting this idea from a site called https://calendly.com/, where those guys made it posible. below is how thier page looks like (user interface)