This is a pretty straight forward change to remove the global front
variable and instead use a couple of accessor functions.
This hopefully will make it easier to keep track and debug when
the front screen changes.
* ensure newly created windows are placed somewhere visible - ie, not
off the screen.
* ensure newly created window sizes aren't insanely large, which end up
being unable to be moved or resized in amiwm.
This has shown up with gtk apps (kicad, firefox) with their load/save
dialog. For some reason they want to be almost 2x my desktop size,
making them super hard to use.
Although it likely doesn't matter /that/ much, the x11 xlib manual
does say to use it rather than expecting the struct to stay the same
size.
Yeah yeah it's 2022 and we really do build things from source,
ICCCM is likely not going to change that much nowdays, etc, etc.
Adrian Chadd