Grouping, collapsing and visual design for activities in timeline

[lklyne]

Overview

Another approach for adding more clarity to high-level views is to give the user control over how activities are grouped on the timeline. This approach lets the user define an approach to groups and subgroups. Every time a group is collapsed inline, a heatmap shows what’s inside the group.

Feature request

• Add additional "grouped" mode which shows collapsable groups in the left part of the timeline.
• Groups and subgroups can be customized and swapped. For example, first group by subsystem, then by decomposition, or first group by layer, then by scheduling goal.
• Collapsed views always show a heatmap.
• Ability to group based on naming structure of activity type.
• At the final group, explore using the packing algorithm we already have, and explore a "show more" for large rows.
• Could also consider adding a pure waterfall mode https://github.com/NASA-AMMOS/aerie-ui/issues/908

https://www.figma.com/file/gsWLcy9UuqSQVqbyHf4Lw6/AERIE-Filtering%2C-Activity-UX%2C-Timeline-Density?type=design&node-id=303-92411&mode=design&t=F0xh0fa4CApC1nli-4

[lklyne]

Related to #1138

[AaronPlave]

Closed by https://github.com/NASA-AMMOS/aerie-ui/pull/1259, @lklyne let me know if you want to re-open