[evcc] Fix API change on duration channels

[MikeTheTux]

[evcc] API change on duration channels

Since EVCC version 0.127.0 (evcc-io/evcc#13319) the EVCC Rest API duration states are in seconds instead of nanoseconds.

Current EVCC implementation still treats them as Nano-Seconds. E.g.:

        long chargeDuration = loadpoint.getChargeDuration();
        channel = new ChannelUID(uid, channelGroup, CHANNEL_LOADPOINT_CHARGE_DURATION);
        updateState(channel, new QuantityType<>(chargeDuration, MetricPrefix.NANO(Units.SECOND)));

Fixes the following issues:

• [evcc] API change on duration channels #17485
• [evcc] "Ladedauer" and "Verbleibende Ladedauer" not working #17432

[lsiepel]

This change looks fine, but it also makes me wonder if we can implement some kind of schema versioning.
As currently the binding mainly supports one evcc version, all users need to be at the same version of both binding and evcc to make it work. Would be nice if we can somehow detect the evcc version and act on it. wdyt?

[MikeTheTux]

EVCC status API provides the version info, e.g. "version":"0.130.13". This could be used to support different versions in parallel. Nevertheless, I fear that I will not be able to implement such a feature in the near future.

[lsiepel]

Thanks, LGTM.

Regarding the versioning, fully understand this is time consuming, good to knwo there is a version string we can depend on. Implementing schema verisoning is not that simple if the remote API hardly supports generic/dynamic structures.