Function attach_to_node_console 

pub async fn attach_to_node_console(
    backend: &StaticBackendDispatcher,
    token: &str,
    site_name: &str,
    xname: &str,
    term_size: TermSize,
    k8s: &K8sDetails,
) -> Result<ConsoleAttachment, Error>

Attach an interactive PTY console to a node.

Callers must validate group-member access for xname and resolve vault/k8s URLs BEFORE calling this; see crate::service::authorization::validate_user_group_members_access.