Closes the one MAJOR from /trekreview of S3.6 (verdict WARN): the
user-facing NOK-string formatter had only an isinstance(...,str) check,
so a regression (wrong divmod, dropped padding, øre/kr transposition,
or non-breaking-space → ASCII) would ship a wrong money figure with the
suite green. Adds a load-bearing value-level test (thousands grouping,
sub-100-øre padding, negative-sign branch) pinning the actual Norwegian
\xa0-separated formatting; verified red under a divmod(...,1000) mutation
and reverted. Suite 333 passed / 4 skipped, ruff+mypy clean.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_0145ZKPLMVeqM47z2jxxokym
