[Auth][OIDC] Transition plan from IdentityModel/Duende

[kazo0]

We need to determine if we can move away from IdentityModel.OidcClient as the underlying implementation for the OidcAuthenticationProvider. This is not deprecated and replaced with Duende IdentityModel and it isn't clear whether we should be moving to this as this may be a paid service.

Need to discuss options with @carldebilly / @nickrandolph

[DevTKSS]

I think OpenIdDict could be a at least free option #2870

Could the team please check if there might be any possibility to get kind of abstraction levels into that, which we then would be able to use already with "just" custom?

Like important would be that there would be a replacement for the Duende package provided secret which includes also having a pkce challenge option or a seperate oAuth2 option could also be an option which we seem to kind of already have for Windows target but not documented or public available through our IAuthenticationService interface