enhance battery report with kWh fleet telemetry data instead of range loss

Currently the battery degradation report is based on range loss since that's all that was available using the v1 data polling service. With the enhanced telemetry migration, the vehicle now report kWh as well.

The kWh loss is more accurate when comparing with fleet data, since it eliminates the uncertainties of specific vehicle configurations such as the use of 18" or 19" wheels for example which have different range profiles for the same kWh battery.

An additional report using "% kWh" battery loss will also allow comparing range loss percentages across the entire fleet irrespective of model and configuration, for example regardless of model 3 long range or short range, or model 3 vs model y, a report like this would give a lot more insight into expected degradation.