Inventory UI Rework

[shiftyscales]

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

The existing inventory UI is old, clunky, and has several known issues.

Describe the solution you'd like

Remaking the inventory UI to be something more fully-featured, and polished.

Describe alternatives you've considered

N/A

Additional Context

Making this issue as a 'hub issue' as a separate work item to track dependencies/blockers related to this work. E.g.: #10 #31 #108 #289 #534 #771 #1105