[Feature Request] Support using auth() with a collection predicate expression

[ymc9]

Here's a scenario:

model User {
    ...
    roles Role[]
}

model Role {
    ...
    permission string
}

The desired policy is:

@@allow('all', auth().roles?[permission == 'ADMIN'])

[ymc9]

Discord thread: https://discord.com/channels/1035538056146595961/1159194942787293255/1168565074374443098

[ymc9]

Before this is implemented, you can use a workaround as shown in this repo: https://github.com/ymc9/zenstack-auth-relation