merge: upstream fixes (mutt/default)

merge: upstream fixes (mutt/default)

 * Remove redraw flag setting after mutt_endwin().
 * Change km_dokey() to pass SigWinch on for the MENU_EDITOR. (see #3877)
 * Separate out the compose menu redrawing. (see #3877)
 * Separate out the index menu redrawing. (see #3877)
 * Prepare for pager redraw separation. (see #3877)
 * Separate out the pager menu redrawing. (see #3877)
 * Don't create query menu until after initial prompt. (see #3877)
 * Silence imap progress messages for pipe-message. (see #3929)
 * Ensure mutt stays in endwin during calls to pipe_msg() (closes #3929)