패키지 버전 업데이트 및 SvelteKit 3, Tailwind CSS 4로 마이그레이션

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

vite.config.ts

@@ -1,12 +1,17 @@
+import adapter from "@sveltejs/adapter-node";
 import { sveltekit } from "@sveltejs/kit/vite";
+import { vitePreprocess } from "@sveltejs/vite-plugin-svelte";
+import tailwindcss from "@tailwindcss/vite";
 import Icons from "unplugin-icons/vite";
 import { defineConfig } from "vite";
 
 export default defineConfig({
   plugins: [
-    sveltekit(),
-    Icons({
-      compiler: "svelte",
+    tailwindcss(),
+    sveltekit({
+      preprocess: vitePreprocess(),
+      adapter: adapter(),
     }),
+    Icons({ compiler: "svelte" }),
   ],
 });