Minor improvements of Win32 code

Yuhang Zhao

2024-12-09 42977738aba59150109fea3e9edd2b74643c1000

 examples/mainwindow/mainwindow.h

@@ -30,8 +30,6 @@
protected:
    bool event(QEvent *event) override;

    void closeEvent(QCloseEvent *event) override;

private:
    void installWindowAgent();
    void loadStyleSheet(Theme theme);