Another consequence of a583fe723 ("commandline -f foo" to skip queue
and execute immediately, 2024-04-08) is that "commandline -f repaint"
will paint the prompt with the current value of $status which might be
set from a shell command in a the currently executing binding, instead of
waiting for the top-level status. This is wrong, at least historically. It
surfaces in bindings like alt-w which always paint a status value of [1]
when on single-lines commandlines.
Another regression is that a redundant repaint in a signal handler outputs
an extra prompt.
Fix both by making repaint commands go over the input queue again. This way,
they are always run with a good commandline state. There is no need to
repaint immediately because I don't think anyone has a data dependency on it
(we currently don't expose the prompt string), it's only for rendering.