Permission to read only and no write

[bilogic]

Hi,

1. I tried adding $permission to the EmailSenderScreen example to test things out:

    public $permission = [
        'systems.email'
    ];

2. However, it prevents the screen from loading with a 403 Forbidden.
3. Is it possible to have a read only permission for the Users/Roles/CRUD in the built-in example?
4. I also cannot see systems.email under Permissions of /admin/users/{id}/edit
5. How do we get new permissions into the Permissions section?
6. Why does resource from https://github.com/orchidsoftware/crud use a different approach?

    public static function permission(): ?string
    {
        return 'email-resource';
    }

Sorry for the numerous questions, but I thought they are inter-related and can give good insights into how permissions were designed.

Thank you.