fix: 调整nuxt测试路径

- 将nuxt测试路径调整到组件旁

app/utils/file.test.ts

@@ -0,0 +1,51 @@
+import {
+  formatFileSize,
+  getFileExtension,
+  formatFileExtension,
+} from '@/utils/file';
+import { expect, test, describe } from 'vitest';
+
+/**
+ * 单元测试: formatFileSize
+ */
+describe('formatFileSize', () => {
+  test('format bytes correctly', () => {
+    expect(formatFileSize(500)).toBe('500.00 B');
+  });
+  test('format kilobytes correctly', () => {
+    expect(formatFileSize(2048)).toBe('2.00 KB');
+  });
+  test('format megabytes correctly', () => {
+    expect(formatFileSize(5 * 1024 * 1024)).toBe('5.00 MB');
+  });
+});
+
+/**
+ * 单元测试: getFileExtension
+ */
+describe('getFileExtension', () => {
+  test('extract extension from filename', () => {
+    expect(getFileExtension('document.pdf')).toBe('pdf');
+  });
+  test('handle filenames without extension', () => {
+    expect(getFileExtension('README')).toBe('');
+  });
+  test('handle multiple dots in filename', () => {
+    expect(getFileExtension('archive.tar.gz')).toBe('gz');
+  });
+  test('handle empty filename', () => {
+    expect(getFileExtension('')).toBe('');
+  });
+});
+
+/**
+ * 单元测试: formatFileExtension
+ */
+describe('formatFileExtension', () => {
+  test('format extension without dot', () => {
+    expect(formatFileExtension('txt')).toBe('TXT');
+  });
+  test('format extension with dot', () => {
+    expect(formatFileExtension('.jpg')).toBe('JPG');
+  });
+});