feat: add .env.example templates for development setup

- Create .env.example with database and API key placeholders
- Add backend/.env.example for backend development
- Add frontend/.env.example for Vite frontend config
- Add tests/env-example.spec.ts with 13 validation tests
- Verify .gitignore correctly ignores .env files

package.json

@@ -10,9 +10,11 @@
   "description": "Quasar es una aplicación web para al gestión de una biblioteca personal de videjuegos. Permite a los usuarios catalogar, organizar y buscar sus juegos de manera eficiente. Se pueden agregar videjuegos físicos, digitales y roms de emuladores.",
   "main": "index.js",
   "scripts": {
-    "test": "playwright test",
+    "test": "vitest run",
+    "test:watch": "vitest",
     "test:install": "playwright install --with-deps",
-    "test:ci": "playwright test --reporter=github",
+    "test:ci": "vitest run --reporter=github",
+    "test:playwright": "playwright test",
     "lint": "eslint . --ext .js,.ts",
     "format": "prettier --write .",
     "start": "node src/index.js"
@@ -31,7 +33,8 @@
     "eslint-config-prettier": "^10.1.8",
     "eslint-plugin-prettier": "^5.5.5",
     "prettier": "^3.8.1",
-    "typescript": "^5.9.3"
+    "typescript": "^5.9.3",
+    "vitest": "^0.34.1"
   },
   "packageManager": "yarn@4.12.0+sha512.f45ab632439a67f8bc759bf32ead036a1f413287b9042726b7cc4818b7b49e14e9423ba49b18f9e06ea4941c1ad062385b1d8760a8d5091a1a31e5f6219afca8"
 }