Running on eglfs platform breaks Ctrl+C and SIGTERM to quit gracefully

[Dregu]

Describe the bug
Running moonlight-qt --platform eglfs stream ... from systemd doesn't make the process exit gracefully with the default systemd KillSignal=SIGTERM, but SIGKILL has to be used. Also the process doesn't respond to Ctrl+C when ran over ssh. Only way to quit gracefully and make use of the --quit-after option is by pressing Ctrl+Alt+Shift+Q, but this is no good for any kind of automation on embedded devices. Forcing the process to close using SIGKILL doesn't respect --quit-after and leaves apps in paused state on host.

On wayland and xorg Ctrl+C and killall moonlight work as expected, triggering the quit segue.

Steps to reproduce

• Have Raspberry Pi 4
• Run moonlight-qt --platform eglfs stream ... in tty1 or over ssh
• killall moonlight-qt or Ctrl+C don't do anything, but killall -9 moonlight-qt is needed

Client PC details (please complete the following information)

• OS: Raspberry Pi OS Bookworm
• Moonlight Version: v6.1.0
• Linux package type: Official moonlight raspbian apt repo

Additional context
I actually fixed this too, at least for my Pi. I'm not making a PR cause I have no idea what I'm doing, if this causes problems for other platforms or if this is even the right thing to do. This does however fix Ctrl+C over ssh and makes stopping the systemd service quit the session gracefully, with --quit-after applied.

void signal_handler(int) {
    SDL_Event event;
    event.type = SDL_QUIT;
    event.quit.timestamp = SDL_GetTicks();
    SDL_PushEvent(&event);
}

bool Session::initialize()
{

    // ...

    // Add signal handlers that something messed up above or didn't create at all
    signal(SIGINT, signal_handler);
    signal(SIGTERM, signal_handler);

    return true;
}