bug#35287: dired-do-copy English beef-up

[積丹尼 Dan Jacobson]

Hmmm, today I tried "carelessly copying some files to / as a regular
user without lifting my eyes up to see if they failed",

 SPC [dired-next-line]
 SPC [dired-next-line]
 C [dired-do-copy]
 / [self-insert-command]
 <return> [exit-minibuffer]
 SPC [dired-next-line]
 SPC [dired-next-line]
 SPC [dired-next-line]
 SPC [dired-next-line]
 C [dired-do-copy]
 / [self-insert-command]
 <return> [exit-minibuffer]
 SPC [dired-next-line]
 SPC [dired-next-line]...

Error messages like
Copy ‘/tmp/.X0-lock’ to ‘/.X0-lock’ failed:
(file-error Opening output file Permission denied /.X0-lock)
I guess were too short to trigger the "?" perhaps,
but anyway, by the time the user types the next SPC any hint of an error
is swept away. Just like I suppose the "type '?' to see more" note would
be.

One might say "well on the shell command line if you don't look up to see
the cp error messages, it is your own fault too."

But at least they will still be sitting on the screen when you finally
look up.

And won't disappear due to a single additional key press, whether if be
from you, keyboard static electricity, a cat / baby walking on it, etc....