Support live collaboration in the Playground #40
Description
It would be nice to add support for live collaboration to the Playground. We could add a "Collaborate" button or similar that would create a collaboration session on the current example e.g. https://eclipse.dev/epsilon/playground/?egx&session=a-guid. One would then share this URL with other users who would then join the editing session from their own browser.
The building blocks for achieving this are already there. One option is to use YJS. This would require us to either change our editors from ACE to Monaco (which already supports collaborative editing through YSJ) or to implement an ACE/YJS binding ourselves.
Regarding the YJS backend, we could start by using the public YJS server (wss://demos.yjs.dev/ws), but we'd eventually need to run our own instance somewhere.