feat: change application style

- change default dark theme to light
- disable dark mode on windows 10 because Qt's windows 11 theme has bad support on windows 10 (icon display error)
- level required minimum qt version up to 6.5 for color schema.

app/graphicsscene.h

@@ -26,6 +26,9 @@ public:
 
     QPixmap renderToPixmap();
 
+public slots:
+    void updateStyle(Qt::ColorScheme colorScheme);
+
 private:
     QGraphicsItem * m_theThing = nullptr;
 };