Frontends meeting guide revision

[JasonWeill]

Based on the Jupyter host guide revised by jupyter/jupyter#731, including contributions from @marthacryan and @ericsnekbytes, I propose revising the top section of our HackMD meeting minutes as follows:

https://gist.github.com/JasonWeill/b722f405b21ce3cea5828dd87241799b

This file is not source controlled, so please leave comments here. Thanks!

[krassowski]

Adding host guide on top of agenda will make it less useful as everyone will need to scroll down over it.

Shall we instead update: https://github.com/jupyterlab/frontends-team-compass/blob/main/docs/host-guide.md ?

Or are you also proposing some changes to the agenda template?

[JasonWeill]

@krassowski I could do that instead! Would make for an easier code review, too.