pub fn verify_flat(
doc: &Document,
fields: &[Field],
placements: &[FlatPlacement],
clusters: &[(f32, f32)],
) -> Result<(), FormsError>Expand description
Verify a flat-form fill: page membership + hand-pinned column-x membership + per-group ordinal-y
descent + the no-unmapped scan. clusters is the per-form hand-pinned logical-column → (min_x0, max_x1) table (measured from the blank PDF). Fails closed.