style: Convert tabs to spaces across Emacs config

lisp/init-startup.el

@@ -1,4 +1,4 @@
-;;; init-startup.el --- startup settings  -*- lexical-binding: t -*-
+;;; init-startup.el --- startup settings -*- lexical-binding: t -*-
 
 ;;; Commentary:
 
@@ -89,6 +89,9 @@
 ;; 优化换行规则
 (setq word-wrap-by-category t)
 
+;; 禁用制表符
+(setq-default indent-tabs-mode nil)
+
 ;; 修改mac键位
 (when *is-mac*
   (setq mac-command-modifier 'meta)