Function get_hardware_cluster 

pub async fn get_hardware_cluster(
    infra: &InfraContext<'_>,
    token: &str,
    params: &GetHardwareClusterParams,
) -> Result<HardwareClusterResult, Error>

Fetch hardware inventory for every member of an HSM group.

When params.group_name is unset, the first group the caller has access to is used and surfaced back through HardwareClusterResult::hsm_group_name. Per-node inventory queries run concurrently, capped by HW_INVENTORY_CONCURRENCY_LIMIT. Empty groups are logged but not treated as an error.