Retry Behavior for SigV4Adapter in REST Catalog

### Feature Request / Improvement

Hi team,

I’ve recently migrated to AWS S3 Tables and switched from using the GlueCatalog to the REST catalog. After updating the catalog configuration, everything works correctly in local, single‑process scenarios. However, I’m encountering intermittent failures when scaling out to multiple Dask workers making parallel requests.
Specifically, I’m seeing occasional `ThrottlingException` errors coming from AWS SigV4‑signed requests. Once throttling occurs, subsequent requests sometimes fail with:
`requests.exceptions.HTTPError: 403 Client Error`

My understanding is that throttled SigV4 signing attempts can lead to follow‑on request failures, resulting in unauthorized S3 operations. According to AWS’s recommendation for handling throttling on signed requests, retry configuration should be applied via botocore: https://boto3.amazonaws.com/v1/documentation/api/latest/guide/retries.html

While reviewing the PyIceberg implementation, I noticed:

- The GlueCatalog sets reasonable default retry settings on the underlying boto session: https://github.com/apache/iceberg-python/blob/main/pyiceberg/catalog/glue.py#L331-L348
- The REST catalog, and specifically the SigV4Adapter, does not appear to configure any retry behavior by default: https://github.com/apache/iceberg-python/blob/main/pyiceberg/catalog/rest/__init__.py#L684-L694

This creates an inconsistency where switching from Glue to REST results in weaker retry behavior, which becomes visible under parallel load.

### Question / Proposal
Should the REST catalog align its default retry behavior with what GlueCatalog already applies?
At present, users can manually configure retry settings by supplying a custom botocore session via catalog properties, but I am yet to test if this works. It seems reasonable and more consistent for the REST catalog to provide safe defaults, especially since SigV4Adapter is now a common path for AWS S3 Tables.

Matching (or at least approaching) the GlueCatalog’s retry policy would provide the following benefits:

- Avoid intermittent throttling‑triggered failures in distributed workloads
- Improve parity between Glue and REST behavior
- Reduce the configuration burden on users switching to REST for AWS‑backed tables

Happy to discuss or test any proposed changes. Thanks for your work on the project!

Vergleiche die Retry-Konfiguration von GlueCatalog in pyiceberg/catalog/glue.py#L331-L348 mit der Konfiguration von REST SigV4Adapter in pyiceberg/catalog/rest/__init__.py#L684-L694 und lies anschließend die im issue verlinkten Hinweise zu botocore-Retries. Prüfe, wie eine benutzerdefinierte botocore-Session über Katalogeigenschaften bereitgestellt wird. Als abgeschlossen gilt die Arbeit, wenn REST-Anfragen über eine vereinbarte sichere Standard-Retry-Policy verfügen und sich das Verhalten bei Throttling und parallelen Workloads konsistent zu Glue verhält.

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