Function analyze_quantities 

pub fn analyze_quantities(
    content: &[u8],
    ids: Option<&HashSet<u32>>,
) -> QuantityAnalysis

Join three canonical opt-in analytic views with exact authored observations. ids selects actual product occurrences; an empty set returns no rows. Source measurements are nominal and intentionally never summed into a product material quantity, cutting length, or physical-part count.