Make inspector tabs/groups focusable from the outside

[PRGfx]

Description

It would be handy to focus a group or at least open the corresponding inspector tab from a plugin.

I was testing Networkteam.ContentComments and created a proof of concept plugin to give the comments in the inspector more visibility, by adding a button to the NodeToolbar, indicating the number of comments and opening the inspector tab.
The implemented "solution" is a big red flag..

Expected behavior

I don't really like the idea of selecting the inspector-tab "in any case" through an action. Imo that would make it extremely awkward to setup the component after it filtered which tabs to actually display and then switch to an actually existing tab.
However I'm not sure what the alternative would be.

Also invoking an action without feedback doesn't feel very satisfying (maybe we want to know if the given tab is not available?)
How could we get the available tabs? Is this suddenly a global state with a selector?

While my original concept was limited to tabs, I think it would be convenient to pass the group or property to avoid resolving this information ourselves..

This could be interesting for an implementation of #675 as well. (Although that would not really be the "outside")