Function write_slice_svg 

pub fn write_slice_svg(
    path: &Path,
    raster: &RgbImage,
    palette: &Palette,
    limits: (f64, f64),
    scale: ScaleMode,
    variable: &str,
    units: Option<&str>,
    long_name: Option<&str>,
    standard_name: Option<&str>,
    time_label: Option<&str>,
    depth_index: usize,
) -> Result<(), Box<dyn Error>>

Write a self-contained SVG containing the map raster, metadata, and a labeled colorbar. The raster is embedded as PNG so the export has no dependency on the source NetCDF file.