Patch Notes: Vulkan blank window fix

Graphics on Windows

After you select Vulkan, the first start asks two questions. The launcher asks first, then the game asks.
If you can see the window, select Keep Vulkan. If the window is blank, select Go back.
With no answer in 20 seconds, DFO Online starts again on Direct3D 11. The next start asks again.
The launcher now has a Graphics part with Use Vulkan. You can turn Vulkan on or off before you play.
After you change it, select Restart to apply.

VULKAN-BLANK, GPU-BACKEND-LAUNCHER: a blank Vulkan window goes back to Direct3D 11; the launcher gets the backend switch by @Lattymoy in #1493

Full Changelog: app-v0.1.13712...app-v0.1.13716