toc_df = reconstruct_toc_from_body(line_df, span_df=span_df, mode="no_toc")
toc_df = reconstruct_toc_from_body(
    line_df, existing_toc_df=native_toc, span_df=span_df, mode="extend_native",
)
toc_df = reconstruct_toc_from_body(
    line_df, existing_toc_df=native_toc, span_df=span_df, mode="composite",
)
toc_df = reconstruct_toc_from_body(line_df, existing_toc_df=native_toc, span_df=span_df, mode="auto")