Very impressive and cool stuff! This shares similar themes to what I'm building over at https://studio.codevideo.io - I also chose to go with an event sourcing solution. I experimented with real time mouse recording but though it was overall too complex for more advanced examples, so for now I've setted with a virtual mouse that you can move from place to place to simulate how it might actually move - I'm curious, how did you solve realtime edits and highlighting directly in the editor? Are you using Monaco editor with realtime highlighting updates somehow? It's something I still haven't implemented in CodeVideo...

Also you could look at how we did it with codecast, it's open source on GitHub search for codecast France ioi With mouse relative position, highlights selections of code etc