Different from the raffle and audit draw demos: instead of picking a subset out of a pool, this produces a complete, verifiable random order for everyone on the list. Fits things like speaker order at a meetup, PR review queue order, standup speaking order, or any "who goes first" decision for a whole group at once.
Locks in the current block height the moment you submit, then waits a couple of
blocks so the eventual order isn't knowable in advance by anyone, including this server. The full
ordering is derived from those future blocks' mix_hash values, using a standard
Fisher-Yates shuffle seeded from the beacon, not a server-side random number.