UI: Match Windows taskbar state to tray icon

This adds both a status icon, and changes the color
of the taskbar button itself.

UI/window-basic-main.hpp

@@ -21,6 +21,10 @@
 #include <QAction>
 #include <QWidgetAction>
 #include <QSystemTrayIcon>
+#ifdef _WIN32
+#include <QWinTaskbarButton>
+#include <QWinTaskbarProgress>
+#endif
 #include <QStyledItemDelegate>
 #include <obs.hpp>
 #include <vector>
@@ -272,6 +276,11 @@ private:
 	QPointer<QMenu> perSceneTransitionMenu;
 	QPointer<QObject> shortcutFilter;
 
+#ifdef _WIN32
+	QWinTaskbarButton *taskBtn = new QWinTaskbarButton(this);
+	QWinTaskbarProgress *taskProg = taskBtn->progress();
+#endif
+
 	QPointer<QWidget> programWidget;
 	QPointer<QVBoxLayout> programLayout;
 	QPointer<QLabel> programLabel;