Refactor/reformat core-ui

+ Move minibuffer fringe disabler to ui/doom
+ Disable blink-cursor-mode (too distracting, causes other issues e.g.
  #892)

core/core-keybinds.el

@@ -60,11 +60,6 @@ If any hook returns non-nil, all hooks after it are ignored.")
   (set-face-attribute 'which-key-local-map-description-face nil :weight 'bold)
   (which-key-setup-side-window-bottom)
   (setq-hook! 'which-key-init-buffer-hook line-spacing 3)
-  (defun doom*no-fringes-in-which-key-buffer (&rest _)
-    (doom|no-fringes-in-minibuffer)
-    (set-window-fringes (get-buffer-window which-key--buffer) 0 0 nil))
-  (advice-add 'which-key--show-buffer-side-window :after #'doom*no-fringes-in-which-key-buffer)
-
   (which-key-mode +1))