WCA Live Nextjs Data Entry

[FinnIckler]

Prototype frontend:

I spend a bunch of time working on the quit_from_round method seeing if it is possible to not introduce a new table for it for quit competitors.

It is definitely possible by handling it like WCA Live does (marking advancing as false in the previous round), but that does lock us into marking rounds as done again.

It's also pretty error prone, at least when you do it in the console manually and you can screw up your whole recomputation functions by having more live_results than registrations.

Working on this prompted me to move the recomputation methods to the round model as they need to be called again when someone is quit from the round. I do think that is a better place for them anyway as it recomputes everything per round and not per live_result