txid-validity

Support for

• txid in cdc struct (_cdc.txid) - for data integrity
• summary.txid-valid-through, summary.txid-max - for data integrity
• parition_by "source_ts_us"
  included

iceberg-kafka-connect-runtime-partitionby-ts-us

adding ts_us as a top level field.

iceberg-kafka-connect-runtime-0.6.19-txid

adding txid in cdc metadata