Function sample_structural_with_overlay 

pub fn sample_structural_with_overlay(
    view: &ModelView<'_>,
    n_rows: usize,
    rng: &mut CausalRng,
    ws: &mut MechanismWorkspace,
) -> Result<(ValueBatch, Vec<f64>), ModelError>

Structural path: sample noise then evaluate with overlays applied post-hoc for hard sets.

Errors

Mechanism failures, or an overlay with a node both hard-set and shifted (see InterventionOverlay::validate).