test(vitest): amplia la suite con test unitari, integrazione, componenti e stress

- aggiunge test per gameState e utilita server
- aggiunge test di integrazione WebSocket
- aggiunge test componenti Vue (ControllerPage/DisplayPage)
- aggiunge test stress su carico WebSocket
- aggiorna configurazione Vitest per includere nuove cartelle e ambiente componenti
- aggiorna script npm e dipendenze di test

package.json

@@ -11,10 +11,13 @@
     "serve": "vite build && node server.js",
     "test": "vitest",
     "test:unit": "vitest run tests/unit tests/integration",
+    "test:component": "vitest run tests/component",
+    "test:stress": "vitest run tests/stress",
+    "test:all": "vitest run",
     "test:ui": "vitest --ui",
-    "test:e2e": "playwright test",
-    "test:e2e:ui": "playwright test --ui",
-    "test:e2e:codegen": "playwright codegen"
+    "test:e2e": "playwright test --config=playwright.config.cjs",
+    "test:e2e:ui": "playwright test --config=playwright.config.cjs --ui",
+    "test:e2e:codegen": "playwright codegen --config=playwright.config.cjs"
   },
   "dependencies": {
     "express": "^5.2.1",
@@ -24,14 +27,17 @@
     "ws": "^8.19.0"
   },
   "devDependencies": {
+    "@axe-core/playwright": "^4.11.1",
     "@playwright/test": "^1.58.2",
     "@types/node": "^25.2.3",
     "@vitejs/plugin-vue": "^4.1.0",
     "@vitest/ui": "^4.0.18",
+    "@vue/test-utils": "^2.4.6",
     "concurrently": "^9.2.1",
+    "happy-dom": "^20.6.1",
     "jsdom": "^28.0.0",
     "vite": "^4.3.9",
     "vite-plugin-pwa": "^0.16.0",
     "vitest": "^4.0.18"
   }
-}
+}