Add support for custom IDP endpoint and client ID

[joaopalet]

No description provided.

[DiogoFerrao]

In general, I think we should document the process of configuring a custom IDP in a README file since its quite different from the others and could be complex.

Maybe this is the correct place to document the process, and then just refer the user to this guide in the flags, instead of cluttering the flag documentation

[joaopalet]

In general, I think we should document the process of configuring a custom IDP in a README file since its quite different from the others and could be complex.

Maybe this is the correct place to document the process, and then just refer the user to this guide in the flags, instead of cluttering the flag documentation

I've added a bit more information to the flags description and have asked a colleague from the IDP for a suggestion on documentation to link.

I'm not sure the README is the right place to document these, but definitely having a page with more information about it makes sense. Maybe creating a page in the STACKIT KB?