* fix(node): read telemetry fields from their block
The telemetry charts matched fields with unanchored regexes over the
whole payload, so "voltage:" also matched "ch1_voltage:" (power_metrics)
and environment_metrics voltage, plotting them as the device voltage.
The same applied to "temperature:" and other shared field names.
Parse each value only inside its own metrics block (device_metrics or
environment_metrics), match the exact field name and accept negative
values (e.g. temperatures below zero).
* feat(node): add power metrics chart
Plot power_metrics telemetry (ch1..ch8 voltage and current) on the node
page. Each channel that reported data gets a voltage series on the left
axis (V) and a dashed current series on the right axis (mA).
The legacy voltage/current fields of environment_metrics, reported by INA
sensors and to be deprecated in favor of PowerMetrics, are shown in the
same chart as "Environment" series.
The chart is hidden when the node sends no power data and supports the
usual expand and CSV export actions. Translations added for en, es, ru.
Pablo Revilla