Rename ‘helpful.el’ to ‘oni-helpful.el’

This is to prevent any confusion about what files are loaded, otherwise the
configuration will provide the helpful feature that the helpful package should
provide.

oni/home/services/emacs/oni-helpful.el

@@ -1,4 +1,4 @@
-;;; helpful.el --- Helpful configuration             -*- lexical-binding: t; -*-
+;;; oni-helpful.el --- Helpful configuration             -*- lexical-binding: t; -*-
 
 ;; Copyright (C) 2023  Tom Willemse
 
@@ -33,5 +33,5 @@
          ([remap describe-variable] . helpful-variable)
          ("C-h T" . helpful--at-point)))
 
-(provide 'helpful)
-;;; helpful.el ends here
+(provide 'oni-helpful)
+;;; oni-helpful.el ends here