Cerbos PDP v0.55.0: Strict evaluation mode, multiple JWTs, and faster conditions

Cerbos PDP v0.55.0 adds strict evaluation mode, which turns runtime errors in policy conditions into explicit denials instead of silent skips. This release also lets auxData carry multiple named JWTs, folds constant expressions at compile time, and upgrades CEL with 21 new expression functions for networking, regex, and sets.