Problem: When we changed startup to wait for the TUI (like a remote UI),
we forgot to set os/input.c:global_fd. That used to be done by
input_start().
Solution: Initialize os/input.c:global_fd before initializing libtermkey
(termkey_new_abstract) so that tui_get_stty_erase() and
friends can inspect the correct fd.
fixes#10134close#10174