Function apply_registration_requirements 

fn apply_registration_requirements<S>(
    root: CommandNodeBuilder<S, SteelCommandRuntime>,
    id: &Identifier,
    root_permission: PermissionExpr,
    derived_root: Option<&PermissionKey>,
    subcommand_permissions: &[Vec<Box<str>>],
    default_access: bool,
    permissions: &mut BTreeSet<PermissionKey>,
) -> Result<CommandNodeBuilder<S, SteelCommandRuntime>, CommandRegistrationError>
where
    S: CommandPermissionSource,