chore: pre-commit fixups (locale, ruff-format, trailing whitespace)

Auto-applied by pre-commit ahead of upstream PR:
- locale/circuitpython.pot regenerated to include the new audioio
  MP_ERROR_TEXT strings ("DAC init error", "TIM6 init failed", etc.)
- ruff-format reflow on the manual audioio test scripts
- Trailing whitespace stripped from results.md

No source-of-record changes; behaviour and APIs are identical.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>