The boot menu uses a column layout on a framebuffer whose width/height
is below [ui] portrait_below (default 800 thousandths): the vector logo
on top, numbered entry cards at the bottom and wrapping status lines.
[ui] layout forces landscape or portrait. qemu-run.py gains
--display-size to test tall panels, and smoke.sh a layout scenario.
Add English and Simplified Chinese documentation under docs/, covering the boot chain, build, boot, debugging, porting, drivers, XNU 4 KiB pages, macOS and device notes. Add the Pages workflow and CNAME. Rename the boot manager from CrabApple to UniXNU across the package, symbols, paths, configuration file and logs. Update README with the documentation badge and CONTRIBUTING link.