Add Lighthouse CI and expand frontend CI/CD

Replace the previous frontend workflow with an expanded Build, Test & Push workflow. Adds a quality-check job (runs on push and PRs to main) that sets up Node.js, installs deps, runs lint/type checks, unit tests (ChromeHeadless), production build and runs LHCI. The docker job now depends on the quality-check job and only runs on pushes to main. Added lighthouserc.json and ignored .lighthouseci, relaxed two ESLint rules (@typescript-eslint/no-inferrable-types and no-explicit-any), and updated package.json (and lock) to include LHCI tooling.

lighthouserc.json

@@ -0,0 +1,11 @@
+{
+  "ci": {
+    "collect": {
+      "numberOfRuns": 1,
+      "staticDistDir": "./dist/playground-frontend/browser"
+    },
+    "upload": {
+      "target": "temporary-public-storage"
+    }
+  }
+}