When launching Blender via blender-launcher.exe, the window briefly
displays incorrectly on startup when using the Vulkan backend. This is
caused by not properly handling the GHOST_kWindowStateFullScreen case.
Previously, even if the window state was set to fullscreen, nCmdShow
would default to SW_SHOWNORMAL or SW_SHOWNOACTIVATE. With this fix,
nCmdShow is explicitly set to SW_SHOWMAXIMIZED when the window is in
fullscreen state, preventing the flicker.
Pull Request: https://projects.blender.org/blender/blender/pulls/141518
f090572ca8