Expose tooltipTitle in all charts

[mcrascal]

Feature Description Add the option for tooltipTitle to all charts (e.g. LineChart, BarChart) etc, per: https://github.com/evidence-dev/evidence/pull/399

Goal of Feature User wants to include period over period metrics as additional information on a line chart. So hovering over a specific date would show change from a prior date to that date. Many other similar use cases.

Current Solution What do you do today to accomplish the goal you described above? Separate chart, or mixed chart

Are you interested in contributing this feature? Yes

[archiewood]

@mcrascal I also feel the need for this kind of additional information

There is often already a title in eg a barchart's tooltip. Would the idea be to override this?

How often would this title field be preferable to either:

• Another field in the tooltip, but not as title
• another series (eg ability to add a line for yoy growth)

[mcrascal]

There is often already a title in eg a barchart's tooltip. Would the idea be to override this?

Yes, idea is the functionality would be the exact same as in scatter plot.

How often would this title field be preferable to either:

• Another field in the tooltip, but not as title
• another series (eg ability to add a line for yoy growth)

I think another field in the tooltip is a good idea, but it'd be a net new feature in addition to this, while this is just bringing the rest of the charts to parity w/ the scatter plot.

I think another series often would be better, but there are going to be cases where this would be handy.