tests: add frontend tests

frontend/spa/package.json

@@ -6,7 +6,11 @@
   "scripts": {
     "dev": "vite --host",
     "build": "vite build",
-    "preview": "vite preview"
+    "preview": "vite preview",
+    "test": "vitest",
+    "test:ui": "vitest --ui",
+    "test:coverage": "vitest --coverage",
+    "test:run": "vitest run"
   },
   "dependencies": {
     "@heroicons/vue": "^2.2.0",
@@ -23,12 +27,18 @@
     "vue-tg": "^0.9.0"
   },
   "devDependencies": {
+    "@testing-library/jest-dom": "^6.9.1",
+    "@testing-library/vue": "^8.1.0",
     "@vitejs/plugin-vue": "^6.0.1",
+    "@vitest/ui": "^4.0.8",
+    "@vue/test-utils": "^2.4.6",
     "autoprefixer": "^10.4.21",
     "daisyui": "^5.3.10",
+    "jsdom": "^27.1.0",
     "postcss": "^8.5.6",
     "tailwindcss": "^4.1.16",
     "terser": "^5.44.0",
-    "vite": "^7.1.12"
+    "vite": "^7.1.12",
+    "vitest": "^4.0.8"
   }
 }