Transform currently logs "X destroys Y." followed by "X creates token: Z."
because the server implements it as DestroyCard + CreateToken events.
- Add Context_TransformCard (protocol extension 1010) to the transform
event batch and a unit test asserting the server attaches it
- Suppress the destroy/create pair and the migration un-attach lines in
the game log, printing one "X transforms Y into Z (P/T)." message
