Function get_node_details 

pub async fn get_node_details(
    infra: &InfraContext<'_>,
    token: &str,
    xnames: &[String],
) -> Result<Vec<NodeDetails>, Error>

Return one NodeDetails per xname in xnames.

Xnames that are present in xnames but missing from any one of the five backend responses still get a row; the affected fields are filled with "Not found" so the per-row position in the returned vector matches xnames after sorting.

The caller is expected to have already validated group access to every xname; this helper does no authorization of its own.