* s3tables: accept .puffin data files for Iceberg v3 deletion vectors
Iceberg v3 writes deletion vectors as Puffin files under a table's data/
directory, so merge-on-read DELETE and UPDATE on v3 tables were refused
with AccessDenied by the table-bucket upload validator.
Fixes#11842
* s3tables: name all accepted data formats in rejection error
The message stopped at .avro even though .lance and now .puffin are
accepted.
* s3tables: cover deletion-vector filenames in data layout test
Uses the names real engines emit: Spark/Iceberg Java
{seq}-{task}-{uuid}-{counter}-deletes.puffin, UUID-suffixed names, and
the same under a partition directory.
Chris Lu
117ea58a83