[Feature]: Single datapoint in line charts

[sqmch]

Describe the feature

Hello!

In the current state, the line chart does not visualize a single datapoint. If your data has one entry, the chart renders but is completely empty as it requires two datapoints to draw a line, however if you hover over the chart, it still catches the invisible datapoint and shows the tooltip. In chartjs for example, this is avoided through having a point/dot rendered for each datapoint in addition to the line. So when there is only one datapoint, you at least see that one dot (and it doesn't mean you have to settle with bumpy lines as a result, if the dot radius is configured the same as the width of the line).

I realize the charts are still in alpha and all, but just wanted to throw it out there as a request, thank you.

Additional information

• I intend to submit a PR for this feature.
• I have already implemented and/or tested this feature.