some cards may permit being recieved on incorrect games
some wcxfulls permit games they shouldn't (tapu koko flags permit USUM
but games released after the distribution window)
lots of wcx lacking restrictions completely
tested flagging USUM rockruff & zeraora
might be worth discarding MysteryGiftVerifier and instead just using
unused fields for prior formats to supply the data.
Checks.cs initially started out small, but over the years it has grown
to handle multiple types of checks. With all these checks next to
eachother, it's hard to see the overall groups. Splitting them up
(potentially further?) allows for more focused maintenance &
understanding.
Not sure if I'm happy with the overall bandaids used (checks no longer
done within LegalityAnalysis so variable repointing is excessively
used), but I'm happier the way it is now compared to the huge Checks.cs
