PostViz.jar GUI Theme fix
This MR fixes the GUI of vader-postviz.jar, still relying on the old swing look and feel, now uses the flat look and feel aswell.
2025-07-03: Due to updates GitLab may be unavailable for some minutes between 13:00 and 17:00.
This MR fixes the GUI of vader-postviz.jar, still relying on the old swing look and feel, now uses the flat look and feel aswell.