When -o is omitted, the output file is auto-named from the run's
start timestamp and the vehicle VIN and placed under ./logs/,
which is created on demand. logs/ is gitignored.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
All fields with a physical unit are now emitted as
{"value": <number>, "unit": "<unit>"} instead of encoding the unit
in the field name. Field names are renamed accordingly (e.g.
chargePower_kW → chargePower). Battery temperature field names are
also fixed to reflect the already-applied K→°C conversion.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>