Function get_hardware_cluster 

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

Fetch hardware inventory for all nodes in a cluster (HSM group).

Concurrently queries hardware inventory for each node, rate-limited by a semaphore.