Function add_node 

pub async fn add_node(
    infra: &InfraContext<'_>,
    token: &str,
    id: &str,
    group: &str,
    enabled: bool,
    arch_opt: Option<String>,
    hardware_file_path: Option<&PathBuf>,
) -> Result<(), Error>

Register a new node, optionally add hardware inventory, and assign it to an HSM group.

Rolls back (deletes the node) if any step after creation fails.