feat(partition): add tooltip

[monfera]

Summary

Adds shape picking calculation, basic event handler and cursor location transform.
It may return multiple items, for example:

• multilayer treemap: it returns all hovered layers (can be less than the total number of layers if the user hovers over what's a gap at a granular level, but inside a rectangle at a less granular level)
• pie/sunburst: we may extend the logic such that it covers the entire pixel (now it covers the corner of the pixel, so currently it'll yield up to one shape)

Checklist

• Any consumer-facing exports were added to src/index.ts (and stories only import from ../src except for test data & storybook)
• This was checked for cross-browser compatibility, including a check against IE11
• Proper documentation or storybook story was added for features that require explanation or tutorials
• Unit tests were updated or added to match the most common scenarios
• Each commit follows the convention

[codecov-io]

Codecov Report

Merging #544 into master will increase coverage by 0.34%.
The diff coverage is 82.92%.

@@            Coverage Diff             @@
##           master     #544      +/-   ##
==========================================
+ Coverage   71.08%   71.43%   +0.34%     
==========================================
  Files         214      214              
  Lines        6215     6269      +54     
  Branches     1150     1200      +50     
==========================================
+ Hits         4418     4478      +60     
+ Misses       1778     1772       -6     
  Partials       19       19

Impacted Files	Coverage Δ
...ypes/partition_chart/layout/viewmodel/viewmodel.ts	13.44% <ø> (ø)	⬆️
...t_types/xy_chart/state/selectors/compute_legend.ts	100% <ø> (ø)	⬆️
src/utils/commons.ts	100% <ø> (ø)	⬆️
src/chart_types/xy_chart/utils/specs.ts	100% <ø> (ø)	⬆️
...es/partition_chart/layout/types/viewmodel_types.ts	80% <ø> (ø)	⬆️
src/utils/geometry.ts	100% <ø> (ø)	⬆️
...types/partition_chart/layout/types/config_types.ts	100% <ø> (ø)	⬆️
...rtition_chart/layout/viewmodel/link_text_layout.ts	10.52% <ø> (ø)	⬆️
...art_types/xy_chart/annotations/annotation_utils.ts	100% <ø> (ø)	⬆️
.../chart_types/partition_chart/layout/types/types.ts	100% <ø> (ø)	⬆️
... and 40 more

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[monfera]

Added data collection for which individual data array elements make up the sunburst slice or treemap rectangle on @markov00's request. The collection and identification of the original Datum elements in the passed-on data array is done via their zero-based indices in the array. Here's an example in case of a three-layer sunburst:

A new story is added, which has more than one input Datum for each (leaf) slice.

[rshen91]

This looks good! I could use some clarification on the positioning of the tooltip when it approaches the end of the canvas - I'm including a giphy that shows the tooltip not adjusting when it is greater than the canvas perimeter (I'm thinking it should pivot to the right of the cursor sooner than it currently is?).

Is this something this PR should address or is there a subsequent PR that will fix it?

[nickofthyme]

LGTM, would be nice to have an interaction VRT for this.