Automated checks after assigning midcomp groups

[timreyn]

The midcomp assignments should flag if there is anyone with problematic assignments, for example if you have a conflicting competing assignment in another room.

[timreyn]

One check to include is whether someone very fast doesn't make top 40 in round 1 of an event, so we can discuss with the stream team if they should be moved to the streamed stage (usually no).