Function sorted 

pub fn sorted(
    qualified: &[Provider],
    needs: &ProviderNeeds,
    matrix: &Matrix,
    speed: Option<(&Need, &SpeedTable)>,
) -> Vec<Sorted>

Order qualified (the result of providers) for a setup UI: by the preferred ids in order of importance (a provider having the first preferred id outranks any that lacks it, whatever the rest), then by measured median time, smaller first, with unmeasured last, then by name. Nothing is dropped: every provider passed in is in the result, with the evidence it was sorted on. speed is the Need naming the workload and environment, and the table; without it nothing is measured.