Code Snippets in Rise

I think you got it wrong, and that their intention was very simple - to show a piece of code, and to alow for copying it for reuse.
To be used in courses that teach coding...

There is no way to currently add any code into Rise, from wriiten answers in other threads. But is is on the roadmap. 
The main issue is that adding codes - that will work well on all\most browsers and all\most devices - is very complex. And the current solution is more into simplifying the rapid authoring for mobile...