doom|hack-local-variables => MODE-local-vars-hook

Uses a less destructive method (the same that Spacemacs uses) than the
one introduced in 13cee68, by introducing MODE-local-vars-hook hooks,
which run after local vars have been initialized.

The old method was to call `hack-local-variables` *before* mode hooks
run, however, this causes variables set by modes to have higher
precedence than local vars, which is unacceptable.

Also moved intero-mode & dante-mode to haskell-mode-local-vars-hook

modules/lang/haskell/+dante.el

@@ -2,7 +2,7 @@
 ;;;###if (featurep! +dante)
 
 (def-package! dante
-  :hook (haskell-mode . dante-mode)
+  :hook (haskell-mode-local-vars . dante-mode)
   :init
   (setq dante-load-flags '(;; defaults:
                            "+c"