Adding Iceberg Support

[byronellis]

This PR adds support for reads and writes via Iceberg to the Java SDK. At the moment this isn't intended to be used as a standalone IO, but rather to be integrated into a forthcoming catalog representation that should make it easier to work with more structured sources.

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[brucearctor]

Great -- thanks for digging in on this @byronellis !

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This pull request has been marked as stale due to 60 days of inactivity. It will be closed in 1 week if no further activity occurs. If you think that’s incorrect or this pull request requires a review, please simply write any comment. If closed, you can revive the PR at any time and @mention a reviewer or discuss it on the [email protected] list. Thank you for your contributions.

[kennknowles]

This was integrated into #30797 and #30805