code: static ChangeEvent transformChangeEventForUser(
        final ChangeEvent<BsonDocument> event,
        final Codec codec
    ) {
      return new ChangeEvent<>(
          event.getId(),
          event.getOperationType(),
          event.getFullDocument() == null ? null : codec.decode(
              sanitizeDocument(event.getFullDocument()).asBsonReader(),
              DecoderContext.builder().build()),
          event.getNamespace(),
          event.getDocumentKey(),
          event.getUpdateDescription(),
          event.hasUncommittedWrites());
    }
docs: Transforms a {@link ChangeEvent} into one that can be used by a user defined conflict resolver.
  @param event the event to transform.
  @param codec the codec to use to transform any documents specific to the collection.
  @return the transformed {@link ChangeEvent}