Refactor code structure for improved readability and maintainability

frontend/package.json

@@ -6,10 +6,14 @@
     "dev": "next dev",
     "build": "next build",
     "start": "next start",
-    "lint": "eslint"
+    "lint": "eslint",
+    "test": "vitest",
+    "test:ui": "vitest --ui",
+    "test:coverage": "vitest --coverage"
   },
   "dependencies": {
     "@hookform/resolvers": "^5.2.2",
+    "@testing-library/dom": "^10.4.1",
     "class-variance-authority": "^0.7.1",
     "clsx": "^2.1.1",
     "date-fns": "^4.1.0",
@@ -24,14 +28,23 @@
   },
   "devDependencies": {
     "@tailwindcss/postcss": "^4",
+    "@testing-library/jest-dom": "^6.9.1",
+    "@testing-library/react": "^16.3.2",
+    "@testing-library/user-event": "^14.6.1",
     "@types/node": "^20",
     "@types/react": "^19",
     "@types/react-dom": "^19",
+    "@vitejs/plugin-react": "^6.0.1",
+    "@vitest/coverage-v8": "^4.1.0",
+    "@vitest/ui": "^4.1.0",
     "eslint": "^9",
     "eslint-config-next": "16.1.6",
+    "jsdom": "^29.0.1",
     "shadcn": "^3.8.5",
     "tailwindcss": "^4",
     "tw-animate-css": "^1.4.0",
-    "typescript": "^5"
+    "typescript": "^5",
+    "vite": "^8.0.1",
+    "vitest": "^4.1.0"
   }
 }