Add internal doom-customize-theme-hook

Ensures custom-set-faces! take effect before any load-theme hooks.

core/core-lib.el

@@ -477,7 +477,7 @@ Each face spec must be in the format of (FACE-NAME [:ATTRIBUTE VALUE]...).
 Unlike `custom-set-faces', which destructively changes a face's spec, this one
 adjusts pre-existing ones."
   `(add-hook
-    'doom-load-theme-hook
+    'doom-customize-theme-hook
     (let ((fn (make-symbol "doom|init-custom-faces")))
       (fset fn
             (lambda ()

core/core-ui.el

@@ -130,7 +130,8 @@ behavior). Do not set this directly, this is let-bound in `doom|init-theme'.")
   "Set up `doom-load-theme-hook' to run after `load-theme' is called."
   (unless no-enable
     (setq doom-theme theme)
-    (run-hooks 'doom-load-theme-hook)))
+    (run-hooks 'doom-customize-theme-hook
+               'doom-load-theme-hook)))
 
 (defun doom|protect-fallback-buffer ()
   "Don't kill the scratch buffer. Meant for `kill-buffer-query-functions'."