wip: move gfx to gfxhook, some borderless window stuff

gfxhook/util.h

@@ -0,0 +1,7 @@
+#pragma once
+
+#include <windows.h>
+
+void gfx_util_ensure_win_visible(HWND hwnd);
+void gfx_util_borderless_fullscreen_windowed(HWND hwnd, LONG width, LONG height);
+HRESULT gfx_util_frame_window(HWND hwnd);