Player/Audience counter/statistics display

[helenvarley]

I've moved this to a discussion since it needs further discusses to decide what the proper implementation would be 👇

[helenvarley]

i've separated this out from #1028 because it is a separate issue really.
here is some information about how we players need to use the statistics:

in real time - backstage & foyer:

• sometimes we need to see which stages players are on, especially newbies who ask us for help but don't tell us what stage they are on; when we have a walkthrough (online workshop) across multiple stages & lose track of where people are; or when we are testing things and want to join someone in a stage they are testing on.
• an interested public person coming to the foyer can see that there is activity, and if they see that there is audience on a live stage that helps them to know that it is a current live event.

in real time - on the live stage:

• players and audience want to know how many others (and who, in the dropdown) are there on the stage with them

after a live performance:

• we want to be able to access the statistics as a log or archive after a live event - this is quite important for documentation & funding. (& currently there is no way to get the statistics after an event)

[helenvarley]

vicki & i have managed to test the statistics on dev-app & it is working well for us entering & leaving stages & the numbers updating in real time in the Stages list and the Foyer. so this is really great!

one thing: the stats display buffers for ages, especially for vicki. is there any way to speed it up?

and, is there any way to have a record of statistics after the live event?