CMake reads CMakePresets.json, which is before it reads CMakeLists.txt.
This causes CMake Error: Unrecognized "version" field if the version of
CMake is older than support for presets, or the version field of
presets.
The fix is to check CMake version in ladybird.sh before trying to create
the build directory.
Co-Authored-By: Andrew Kaster <andrew@ladybird.org>
We depend on GNU-specific du switch `--apparent-size`. Busybox has this
implemented, but as `-b` instead.
Another part of the build system uses `cp --preserve=timestamps`. This
can be replaced by `rsync -t`, and rsync is already used through the
file.
Thanks to those changes, Serenity can be built on a Busybox system,
without GNU coreutils.
* `chmod -x` as it's for sourcing, not for executing
* Remove run line, for the same reason
* Rename it from .shell_include.sh to shell_include.sh, since e.g.
`rg` doesn't search in hidden files by default
No behavior change.
