Missing icons for Kunos apps 2024-12-07

This adds icons for all Kunos system apps that did not have them.

They are copied or derived from existings graphics from the content/gui folder.

Xbox controller (product picture redrawn) and OpenVR (SteamVR app icon) are new.

Extract them to ./content folder, optionally omitting the subdirectory "ProjectFile". The files that can be overwritten are corrections and to align for consistency (TyreTester and Python).