Support Concurrency Safety Validation: Implement `validateNoNewDeletesForDataFiles`

[sungwy]

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 validateNoNewDeletesForDataFiles function. The Java Reference can be found here

[yingjianwu98]

Hey @sungwy
I can start working on this, thanks!

[Fokko]

@stevie9868 Sure thing!

[sungwy]

Hi @stevie9868 I will get this issue assigned to you! @gabeiglio accurately pointed out that this validation shares much of the underlying logic with #1930 and has expressed interest in working on the underlying building block equivalents like the DeleteFileIndex object that is found in the java reference code.

I'm just bringing this up here so we can share information, coordinate and avoid duplicating the same work.

slack conversation: https://apache-iceberg.slack.com/archives/C029EE6HQ5D/p1750807741550099?thread_ts=1750800752.732089&cid=C029EE6HQ5D

[github-actions]

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[github-actions]

This issue has been closed because it has not received any activity in the last 14 days since being marked as 'stale'