partial overwrite operation

[kevinjqliu]

Rationale for this change

Are these changes tested?

Are there any user-facing changes?

[Fokko]

Ahh thanks @kevinjqliu I don't think we've really implemented this properly.

Java produces:

{
    "added-data-files": "1",
    "added-files-size": "707",
    "added-records": "2",
    "app-id": "local-1743678304626",
    "changed-partition-count": "1",
    "deleted-data-files": "1",
    "deleted-records": "3",
    "engine-name": "spark",
    "engine-version": "3.5.5",
    "iceberg-version": "Apache Iceberg 1.8.1 (commit 9ce0fcf0af7becf25ad9fc996c3bad2afdcfd33d)",
    "removed-files-size": "693",
    "spark.app.id": "local-1743678304626",
    "total-data-files": "3",
    "total-delete-files": "0",
    "total-equality-deletes": "0",
    "total-files-size": "1993",
    "total-position-deletes": "0",
    "total-records": "4"
}

[kevinjqliu]

Closing in favor of #1879