There's been a lot of continued interest in using multiple PyIceberg applications concurrently and having proper support for optimistic concurrency. I think the best place to start is through the implementation of the individual validation functions This subtask tracks the implementation of `validateNoNewDeleteFiles` function. [Java Reference](https://github.com/apache/iceberg/blob/9fc49e187069c7ec2493ac0abf20f73175b3df89/core/src/main/java/org/apache/iceberg/MergingSnapshotProducer.java#L544-L552)