Caching and accelerating meson builds

mold is an easy win, with the following native file: 1 [binaries] 2 c_ld = 'mold' 3 cpp_ld = 'mold' 4 fortran_ld = 'mold' 5 [built-in options] 6 # mold 1.11.0 or later needed due to https://github.com/rui314/mold/issues/1017 7 # --no-as-needed temporarily necessary due to the seeming return of https://github.com/rui314/mold/issues/1017 8 c_link_args = ['-fuse-ld=mold', '-Wl,--no-as-needed'] 9…