Better entitlement framework in V3

[manasag]

Currently, Hasura uses role based access control, where you define the entire set of permissions per-role. However, this doesn't scale well because:

It's not always possible to capture all possible states in the authorization system as separate roles.
It's not possible to reuse permissions (allowed fields, model predicate) across roles.
For complicated permissions, it's hard to verify the correctness of a model's permissions predicate at a glance.

RFC on the proposal can be followed here #10237

V2 Issues that can be addressed by this proposal:

• Create permission check with a session variable in the LHS #3685
• Feature request: Allow checking of values in JWT against fixed strings #1919
• Derived Permissions #3544

[rahulagarwal13]

Related GH Issue - #10310