Function find_rows_above_threshold 

pub fn find_rows_above_threshold(
    baseline: &[Precision],
    current: &[Precision],
    threshold: Precision,
) -> Vec<AnomalyRow>

Return only the rows whose anomaly score exceeds threshold. Useful as the boundary-crossing primitive for change-driven activation: an agent stays asleep until at least one entry crosses the threshold.

• O(n) time, O(matches) space.

Panics if baseline.len() != current.len().