scale to many simulatenous watchers

[arvid220u]

the server as written now scales super poorly to many watchers.

one super hacky solution which i'm not even sure works would be to live-stream the replay file to youtube/twitch/smth in an encoded format, and then have the frontend hook into the live-stream and decode the video into a json format. this way we can do scaling without getting more servers.

a more boring solution is to actually write a scalable server. probably want to switch away from python then, to go/rust/c++.