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/package.json

@@ -6,6 +6,7 @@
     "dev": "next dev --turbopack",
     "build": "next build",
     "start": "next start",
+    "test": "vitest run",
     "type-check": "tsc --noEmit"
   },
   "dependencies": {
@@ -20,10 +21,16 @@
   },
   "devDependencies": {
     "@tailwindcss/postcss": "^4.0.0",
+    "@testing-library/jest-dom": "^6.9.1",
+    "@testing-library/react": "^16.3.2",
+    "@testing-library/user-event": "^14.6.1",
     "@types/react": "^19.0.0",
     "@types/react-dom": "^19.0.0",
+    "@vitejs/plugin-react": "^6.0.2",
+    "jsdom": "^29.1.1",
     "postcss": "^8.0.0",
     "tailwindcss": "^4.0.0",
-    "typescript": "^5.5.0"
+    "typescript": "^5.5.0",
+    "vitest": "^4.1.9"
   }
 }