Historical chart-data.js retained as an example from the original project.
This is sample history, not current readings for a new installation.
It is not loaded automatically and never replaces assets/components/growattstats/data/.
The installed component writes real readings to chart-data.json.
Legacy import: on a new installation with no history, place this file as
assets/components/growattstats/data/chart-data.js and open the chart once.
Only do this deliberately: the example belongs to a different historical dataset.
