로딩 스피너 변경

frontend/app/(main)/main/page.tsx

@@ -2,8 +2,6 @@
 
 import { Card, CardContent } from "@/components/ui/card";
 import { Badge } from "@/components/ui/badge";
-import { Button } from "@/components/ui/button";
-import { RefreshCw } from "lucide-react";
 
 /**
  * 메인 페이지 컴포넌트
@@ -12,23 +10,6 @@ import { RefreshCw } from "lucide-react";
 export default function MainPage() {
   return (
     <div className="space-y-6">
-      {/* Header */}
-      <div className="flex items-center justify-between">
-        <div>
-          <h1 className="text-3xl font-bold">대시보드</h1>
-          <p className="text-muted-foreground">PLM 시스템의 주요 현황을 확인하세요</p>
-        </div>
-        <Button
-          variant="outline"
-          onClick={() => {
-            console.log("refresh");
-          }}
-        >
-          <RefreshCw className="mr-2 h-4 w-4" />
-          새로고침
-        </Button>
-      </div>
-
       {/* 메인 컨텐츠 */}
       {/* Welcome Message */}
       <Card>

frontend/components/auth/AuthGuard.tsx

@@ -3,7 +3,6 @@
 import { useEffect, ReactNode, useState } from "react";
 import { useRouter } from "next/navigation";
 import { useAuth } from "@/hooks/useAuth";
-import { LoadingSpinner } from "@/components/common/LoadingSpinner";
 
 interface AuthGuardProps {
   children: ReactNode;