chore: Authz should support non-named roles (#5855)

* chore: Authz should support non-named roles

Named roles are a construct for users to assign/interact with roles.
For authzlayer implementation, we need to create "system" users.
To enforce strict security, we are making specific roles with
the exact required permissions for the system action.
These new roles should not be available to the user. There is a
clear code divide with this implementation that allows a RoleNames
implemenation for users to user, and system users can create their
own implementation

coderd/rbac/authz_test.go

@@ -13,7 +13,7 @@ import (
 
 type benchmarkCase struct {
 	Name   string
-	Roles  []string
+	Roles  rbac.RoleNames
 	Groups []string
 	UserID uuid.UUID
 	Scope  rbac.ScopeName