Support/Integration with Tab Groups

[coolharsh55]

Starting with v137 Firefox has native support for tab groups where multiple tabs are labelled with a group name and can be collapsed/closed together. While this replicates some functionality of winger, there is still potential use for winger with/beyond the tab group functionality:

1. winger shows all tab groups across windows and makes it easy to switch to them
2. winger provides an alternative interface for interacting/moving tabs to groups -- as currently the only way to do this in firefox is manually right clicking and selecting move to group or drag+drop
3. winger provides window management (naming, stashing) and access to minimised windows/tabs