chore(04-01): install and configure Vitest test infrastructure for apps/web

- Add vitest, @testing-library/react, @testing-library/jest-dom, jsdom, @vitejs/plugin-react as dev deps
- Create vitest.config.ts with jsdom environment and @ path alias
- Create test setup file importing jest-dom/vitest matchers
- Add test scripts to apps/web and root package.json
- Add test task to turbo.json pipeline

apps/web/vitest.config.ts

@@ -0,0 +1,17 @@
+import react from '@vitejs/plugin-react';
+import { resolve } from 'node:path';
+import { defineConfig } from 'vitest/config';
+
+export default defineConfig({
+  plugins: [react()],
+  resolve: {
+    alias: {
+      '@': resolve(__dirname, './src'),
+    },
+  },
+  test: {
+    environment: 'jsdom',
+    globals: true,
+    setupFiles: ['./src/test/setup.ts'],
+  },
+});