Fix the proxy issue in the Mac Qt version

We need to address a recurring proxy issue in the Mac Qt version of our VPN client. At present, the Mac client only routes traffic from the browser through the VPN, while other applications on the system are not proxied correctly. Our goal is to implement a TUN mode or a specialized VPN extension that ensures the entire operating system—rather than just the browser—routes network traffic through the VPN, thereby achieving full system-level coverage.