Re-add Project/Outline icons and colours from GNATStudio 2020

[Cre8or]

I've been using GNATStudio 2020 for some time, and felt the desire to try out the latest (2024) release. One of the things that immediately stood out to me was the lack of colours/icons in the Project and Outline tabs:

At first I thought I was remembering things wrong, but sure enough, checking back in the 2020 version, things look quite different:

(You may notice that I'm using an extended code highlighting plugin, but that's not relevant here.)

So why did this change occur? In the 2024 version, I'm struggling to tell apart types, subprograms, child packages and variables from one another in the Outliner. Likewise, folders belonging to the project cannot be distinguished from with'd library projects in the Project tab, making navigation more difficult. All of this is significantly easier in the 2020 version.

Assuming there isn't a strong justification for this change, could we have the old style back in future versions? For me this is unfortunately bothersome enough to stay on 2020, as some of my packages have grown fairly large, and I would prefer not to waste time on file navigation.