This epic tracks supporting the new added ironic-shard feature in a future release of OSP.

https://specs.openstack.org/openstack/nova-specs/specs/2023.2/approved/ironic-shards.html

This feature was developed as part of Openstack 2023.2 bobcat and by default would be part of a future osp 19 release if supported. part of this epic involves evaculate if this is downstream backporable for inclusion in 18.

18 is antelope with select bobcat backports. The ironic support for this feature landed
in antelope but the nova use of the ironic feature was merged in bobcat.