Add attributedText property to Message

[singpolyma]

Instead of a styler which runs on every render, pre-style the text and store it styled so that it can be rendered that way.

[matthewrfennell]

Hi @singpolyma, is the motivation to keep the API the same while improving performance? Or are you interested in changing the API too?

I.e. would you like to replace text: String with text: AttributedString and pass that directly from the client? Or would you still like to pass a String and just have the AttributedString cached on the Message instead of running the styler in each view?

[singpolyma]

I would like to have both, yeah. Especially so edit can still work until/unless there is a rich text edit option

[singpolyma]

prototype https://github.com/singpolyma/Chat/commit/c9803cc40354419d0742082ec1aba6e05ee8e61e