Use this instead of covnmr_analyze when the result has to be defensible.
Pass `smiles` and the structure verification becomes a recorded step;
`output_path` writes the trail to disk.

THE HASHES ARE TAKEN OVER THE COMPLETE OUTPUT, BEFORE ANY TRUNCATION, so
the trail attests to what was produced rather than to what fitted in the
response -- `hashed_before_truncation` is returned as the standing
statement of that. The peak and integral lists in the response are capped
at `max_rows` (500) with `peaks_truncated` / `integrals_truncated` flags.

The FILE settles the nucleus and the match window follows it, so an APT is
verified as carbon at the carbon tolerance, not at the proton one. Measured
on a real APT the trail records nucleus 13C with nucleus_source "file" --
both when no `nucleus` was given and when "1H" was requested; the argument
is a hint, the acquisition header decides.