[FEATURE] Include identifier field as search facet

Change-Id: I6a0612de5dc7c43bc0ea7a95833a69b7bcfc9682
Releases: 3.0.0
Resolves: #59328
Reviewed-on: https://review.typo3.org/30552
Reviewed-by: Fabien Udriot
Tested-by: Fabien Udriot