User Story

As a user,
I want to see a visual indicator on the compass-shell top bar that shows that a command is currently in progress,
so that I can easily check on the progress even when the shell is collapsed.

Acceptance criteria

• When I run `while(true) {}` in compass-shell, a loading/progress indicator is shown on the compass-shell top bar.
• When compass-shell is collapsed, and a command is in progress, the progress indicator is still shown.
• When a command ends, the in progress indicator is no longer present