ci: publish frontend test and coverage reports

frontend/package.json

@@ -9,7 +9,8 @@
     "lint": "eslint .",
     "preview": "vite preview",
     "test": "vitest run",
-    "test:watch": "vitest"
+    "test:watch": "vitest",
+    "test:coverage": "vitest run --coverage"
   },
   "dependencies": {
     "react": "^19.2.6",
@@ -25,6 +26,7 @@
     "@types/react": "^19.2.14",
     "@types/react-dom": "^19.2.3",
     "@vitejs/plugin-react": "^6.0.1",
+    "@vitest/coverage-v8": "^4.1.11",
     "eslint": "^10.3.0",
     "eslint-plugin-react-hooks": "^7.1.1",
     "eslint-plugin-react-refresh": "^0.5.2",