gui_toolkit 0.42.1

Added

• render.surface_init(r, &s, hwnd, size, ...) -> ok makes a Surface in the one the program points to. surface_create (which returns it by value) is kept and calls it. A Surface is several kilobytes (Present_State's ring of 256 frames): held in a local and copied into a record, -o:speed -debug split it into 12 612 values with a debug record each, and LLVM spent more than ten minutes on that module (Wren's development build and its CI did, until it called surface_init). The doc of surface_create says so.