Add a way to map claims to contextual tuples in the OpenFGA Access Control features

[aaguiarz]

OpenFGA currently supports a way to specify per-application permissions with the Access Control feature https://openfga.dev/docs/getting-started/setup-openfga/access-control.

The feature allows defining a custom model, where, for example, applications can be grouped by audience, or in application role/groups, and have permissions to different stores based on those.

In some cases, it's possible to get the Identity Provider that issues tokens to add claims that specify those relations (audience, application_roles).

It would be helpful to allow configuring the Authorization Control feature to map the token claims to contextual tuples, to avoid having to synchronize that data in OpenFGA.