feat(frontend): scaffold PWA with LiveKit join flow

Vite + React + TS + Tailwind v4, installable PWA. Join-pod UI that fetches a
LiveKit token from the backend, connects to the pod room, and publishes screen
+ mic so PodMan can watch.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

frontend/package.json

@@ -0,0 +1,27 @@
+{
+  "name": "@podman/frontend",
+  "version": "0.0.0",
+  "private": true,
+  "type": "module",
+  "scripts": {
+    "dev": "vite",
+    "build": "tsc --noEmit && vite build",
+    "preview": "vite preview",
+    "typecheck": "tsc --noEmit"
+  },
+  "dependencies": {
+    "@podman/shared": "workspace:*",
+    "livekit-client": "^2.20.0",
+    "react": "^19.2.7",
+    "react-dom": "^19.2.7"
+  },
+  "devDependencies": {
+    "@tailwindcss/vite": "^4.3.1",
+    "@types/react": "^19.2.17",
+    "@types/react-dom": "^19.2.3",
+    "@vitejs/plugin-react": "^6.0.3",
+    "tailwindcss": "^4.3.1",
+    "vite": "^8.1.0",
+    "vite-plugin-pwa": "^1.3.0"
+  }
+}