Ability to have legend values display "now" values

[scop]

Checklist

• I am running the latest version of the card
• I checked if there isn't another feature request opened with the same request
• I checked that the feature is not already available in the dev branch

Is your feature request related to a problem? Please describe.

It would be nice if there was a way to make values in the legend be the ones from now, instead of from the end of the series. End of series values tend to be misleading, and I think most people would expect to see the "now" value in them instead.

Describe the solution you'd like
Maybe legend_value: "now"?

Describe alternatives you've considered
Hiding values from the legend can be done with legend_value: false. That's not nice, but often better than showing the last (misleading) value.

Additional context
N/A