use org-ai-on-region-or-buffer instead of org-ai-on-region

[LemonBreezes]

Hi. I'm thinking we should replace org-ai-on-region with a new command, org-ai-on-region-or-buffer which uses the entire buffer if a region is not selected.

;;;###autoload
(defun org-ai-on-buffer ()
  (interactive)
  (save-mark-and-excursion
    (mark-whole-buffer)
    (call-interactively #'org-ai-on-region)))

;;;###autoload
(defun org-ai-on-region-or-buffer ()
  (interactive)
  (if (region-active-p)
      (call-interactively #'org-ai-on-region)
    (call-interactively #'org-ai-on-buffer)))

I like the implementation above because the user can see that the entire buffer is selected for the command.

[rksm]

ok, will add that, thanks!