Feature Request: Please divide "Anbieterkennung als Präfix für IDs verwenden" Option into two: for UserID and GroupIDs seperately

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Feature request

Which Nextcloud Version are you currently using:
33.0.3

Is your feature request related to a problem? Please describe.
I'm using Keycloak to login existing Nextcloud and Keycloak Users into the Nextcloud (used sociallogin, mirating to user_oidc now so far). The Existing Users already have a User-ID in my Nextcloud, where "keycloak-" is prepended to the UserID of the Keycloak UserID, so I have to use the Option "Anbieterkennung als Präfix für IDs verwenden", to keep the Users that are already in the Nextcloud and in Keycloak. (otherwise Nextcloud would create a new User for existing Keycloak Users and the (keycloak/nextcloud)-User would lose his/her Files).
I'm also using the Option "Gruppenbereitstellung verwenden", to create Groups I'm using in the Nextcloud from Groups in the Keycloak.

My goal is, to match the Keycloak Group nextcloud_admin to the admin Group in the Nextcloud.

This is neccessary, because I'm also using other Clients with my Keycloak, and I don't want the users of other Clients to be admin, when they are admin in the Nextcloud.

Therefore I use:

1. the oidc_groups_mapping App, to map keycloak Group Names to new Nextcloud Group Names.
2. the Whitelist of user_oidc to fit the Groups I'm using in the Nextcloud.

I also activated the Option "Preserve existing group display names" in the oidc_groups_mapping app. This produces the following Problem

A group called nextcloud_admin gets mapped to the group admin in the Nextcloud by the oidc_groups_mapping app, which is in the Group Whitelist of user_oidc,
but then, because of the Option "Anbieterkennung als Präfix für IDs verwenden" from user_oidc App the "keycloak-" Präfix is added to the Groupname. :(
This is very bad, because nextcloud_admin Group members in Keycloak shoud indeed match to "admin" Group in Nextcloud, and not to the "keycloak-admin" Group.

If I leave out the Option "Preserve existing group display names" from the other App (oidc_groups_mapping) the following happens, as far as I see it:

Then there are two groups called "allewesen" in the Nextcloud, from which one is the original Group, already existing in my Nextcloud Setup and the other one is the new one, having the Name "keycloak-allewesen" and the DisplayName "allewesen". This is also very bad, because the admin would not be in the real admin group finally.

Describe the solution you'd like
That is the Problem, my Feature Request is now: Please divide the Option "Anbieterkennung als Präfix für IDs verwenden" into two Options: "Anbeierkennung als Präfix für die UserID verwenden" and "Anbieterkennung als Präfix für GruppenIDs verwenden". This would solve my Problem, as I could then select the UserID Option and deselect the GroupIDs Option.

Describe alternatives you've considered
I tried to cofigure Keycloak to add a "keycloak-" Prefix in front of the UserID, but I didn't find a smart Solution for it.

Additional context
I'm migrating my Nextcloud and Keycloak Setup from the sociallogin Nextcloud App to the user_oidc Nextcloud App, because the user_oidc App supports a better Logout from the Services than the sociallogin App. But in sociallogin the Group Mapping was supported by default.

Start by tracing the user_oidc option "Anbieterkennung als Präfix für IDs verwenden" and the group provisioning and whitelist flow described in the issue. Separate the user-ID and group-ID behavior, then verify that users retain the provider prefix while mapped groups can keep their existing IDs, including the admin group case.