Dynamic calendar feed per city

[ponny]

Is your feature request related to a problem? Please describe.
Juli did a thing with a simple calendar:
https://rubyau.slack.com/archives/C08CG7AKKLZ/p1749469963812489

It'd be nice to have a similar thing that's dynamic based on the meetups once they're in the [location].ruby.org.au microsites (per city).

Describe the solution you'd like
A calendar feed I can add to Gmail and see when Ruby meetups are on per-city. If it updated to show what talks were on, etc that'd be extra nice.

Maybe
If you also included things like the the pidapipo run, that might get more people along too.