chore(use-package): use :preface in favor of :init when defining things

modules/projects/siren-all-the-icons.el

@@ -16,15 +16,17 @@
 (use-package all-the-icons-ibuffer
   :after all-the-icons
   :if window-system
-  :init (all-the-icons-ibuffer-mode 1))
+  :init
+  (all-the-icons-ibuffer-mode 1))
 
 (use-package all-the-icons-completion
   :after (marginalia all-the-icons)
+  :if window-system
   :hook (marginalia-mode . all-the-icons-completion-marginalia-setup)
   :init
   (all-the-icons-completion-mode)
-  :config
 
+  :config
   ;; Override default category lookup function.
   (defun all-the-icons-completion-get-icon (cand cat)
     "Return the icon for the candidate CAND of completion category CAT."

modules/projects/siren-neotree.el

@@ -26,7 +26,7 @@
   (neo-vc-integration '(face char))
   (neo-window-width 54)
 
-  :init
+  :preface
   (defun neotree-project-dir ()
     "Open NeoTree using the project root, using find-file-in-project,
 or the current buffer directory."

modules/projects/siren-treemacs.el

@@ -30,7 +30,7 @@
   (treemacs-last-error-persist-file
    (expand-file-name "treemacs-persist-at-last-error" siren-cache-dir))
 
-  :init
+  :preface
   (defgroup siren-treemacs nil
     "Siren specific settings for treemacs."
     :group 'treemacs)