Previously it was possible to open a link like /home/anon/Desktop/Home,
leading to a folder with the same name. Now it correctly opens its real
path, which is /home/anon
FileManager: Use Core::File::real_path_for to get real path of links
Now that WindowServer broadcasts the system theme using an anonymous
file, we need clients to pledge "recvfd" so they can receive it.
Some programs keep the "shared_buffer" pledge since it's still used for
a handful of things.
