Consider hinting SDL videodriver when Linux wayland

See [available videodrivers](https://wiki.libsdl.org/SDL2/FAQUsingSDL).

Currently SDL2 uses `x11` video driver, even when the current system executing it is on a wayland display server.

Some have reported less problems when using wayland (by setting the `SDL_VIDEODRIVER` environment variable) than allowing the `x11` video driver to use emulated xwayland.

Consider:

- Check if `SDL_VIDEODRIVER` is already set, if not proceed (we want to respect users choice).
- Fetch information on whether the current display driver is wayland (one way is to check whether `WAYLAND_DISPLAY` environment variable is set, also check were not in x11, but there might be better ones)
- Before `SDL_Init()`, pass the `wayland` [hint](https://wiki.libsdl.org/SDL2/SDL_HINT_VIDEODRIVER) using [sethint](https://wiki.libsdl.org/SDL2/SDL_SetHint)

Locate the SDL_Init() entry point and inspect the surrounding startup path before considering SDL_SetHint(). Check how SDL_VIDEODRIVER, WAYLAND_DISPLAY, and X11 environment state are handled; done means setting the wayland video-driver hint only when no explicit SDL_VIDEODRIVER choice exists and the process is running under Wayland.

Written by the indexing model from the issue text.