feat(frontend): add P2 quality gates

apps/frontend/package.json

@@ -7,7 +7,10 @@
     "dev": "vite",
     "build": "vue-tsc -b && vite build",
     "preview": "vite preview",
-    "typecheck": "vue-tsc --noEmit -p tsconfig.app.json"
+    "typecheck": "vue-tsc --noEmit -p tsconfig.app.json",
+    "lint": "eslint .",
+    "format": "prettier --write .",
+    "format:check": "prettier --check ."
   },
   "dependencies": {
     "@types/qrcode": "^1.5.6",
@@ -18,11 +21,18 @@
     "vue-router": "^4.5.1"
   },
   "devDependencies": {
+    "@eslint/js": "^10.0.1",
     "@types/node": "^24.12.0",
     "@vitejs/plugin-vue": "^6.0.5",
     "@vue/tsconfig": "^0.9.0",
+    "eslint": "^10.3.0",
+    "eslint-config-prettier": "^10.1.8",
+    "eslint-plugin-vue": "^10.9.1",
+    "globals": "^17.6.0",
+    "prettier": "^3.8.3",
     "sass": "^1.99.0",
     "typescript": "~5.9.3",
+    "typescript-eslint": "^8.59.3",
     "unplugin-auto-import": "^21.0.0",
     "unplugin-vue-components": "^32.0.0",
     "vite": "^8.0.7",