ci: add code check badges and coverage reports

userfront-e2e/package.json

@@ -11,9 +11,12 @@
     "test:ui": "playwright test --ui",
     "serve:build": "node ./scripts/serve-userfront-build.mjs",
     "build:userfront:wasm": "cd ../userfront && flutter build web --wasm --release && cd .. && node userfront/scripts/optimize-web-build.mjs userfront/build/web",
+    "lint": "biome check .",
+    "lint:fix": "biome check . --write",
     "test:wasm": "npm run build:userfront:wasm && npm test"
   },
   "devDependencies": {
+    "@biomejs/biome": "2.4.16",
     "@playwright/test": "^1.58.2",
     "@types/node": "^24.3.0",
     "typescript": "^5.9.2"