Bulk implementation returning individual results

This is the client counter part of MDEV-30366: permit returning individual results.
This will permit to :

return exact all auto increment id
return individual update rows, permitting "Optimistic locking" batching.
This will permit to have a transparent use of BULK compare to unitary sending all updates.

see c/c implementation https://github.com/mariadb-corporation/mariadb-connector-c/commit/abce07da2ad256c5be2b9d7cc222cccb8cdc6163
(new capability MARIADB_CLIENT_BULK_UNIT_RESULTS + bulk flag STMT_BULK_FLAG_SEND_UNIT_RESULTS)