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

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

src/routes/+layout.svelte

@@ -1,5 +1,5 @@
 <script lang="ts">
-  import { getDownloadingFiles, getUploadingFiles } from "$lib/modules/file";
+  import { getDownloadingFiles, getUploadingFiles } from "#lib/modules/file/index.js";
   import "../app.css";
 
   let { children } = $props();