Support data sequence numbers in REST scan tasks #834

REST-planned FileScanTask currently parses first-row-id from the embedded data-file JSON, but the REST scan-task payload does not expose the manifest-entry data sequence number.

For v3 row lineage readers, _last_updated_sequence_number inheritance needs the data file data sequence number. Without it, REST-planned tasks can pass first_row_id but cannot inherit _last_updated_sequence_number for files that omit or store null row-lineage columns.

Follow-up from #822. The PR adds a skipped test, FileScanTasksFromJsonTest.RowLineageSequence, that should be enabled once REST scan-task JSON can carry this value.