Function stereo_rectify 

pub fn stereo_rectify(
    rig: StereoRig,
    width: usize,
    height: usize,
) -> VisionResult<StereoRectifyMaps>

Builds left/right absolute remap grids that make epipolar lines horizontal.

Callers feed these maps into warp::remap. Identical fronto-parallel cameras with a pure +X baseline produce identity remaps.