Publication of a metadata record -> mdb:MD_Metadata/mdb:dateInfo with cit:dateType = publication

An idea for enhancement and compliance with ISO19115-3 (mdb):

When a metadata record is published, a timestamp could be written into metadata as `mdb:MD_Metadata/mdb:dateInfo` with` cit:dateType = publication`.

ISO 19115-1 allow multiple `mdb:dataInfo` in `mdb:MD_Metadata` each having a `cit:dateType` from http://standards.iso.org/iso/19115/resources/Codelists/cat/codelists.xml#CI_DateTypeCode

GeoNetwork writes - as far as I can see - two `mdb:dateInfo` into metadata - one with cit:dateType=creation and one with cit:dateType=revsion.

But why isn't a mdb:dateInfo with cit:dateType=publication written when a metadata record is published and deleted when the same record is unpublished?

Example of 3 `mdb:MD_Metadata/mdb:dateInfo`:
```



2024-02-14T14:20:22.506084Z









2025-05-23T18:44:25.155156Z









2025-05-23T18:44:25.155156Z






```

No source file, test, or entry point is named. Trace the metadata publication and unpublication workflow first, then verify that publication adds a cit:dateType=publication dateInfo and unpublication removes it while existing creation and revision dates remain unchanged.

Written by the indexing model from the issue text.