Phase 3: scaffold Manager Dashboard — all pages, layout, routing

Includes: LoginPage (PIN pad), DashboardPage (30s polling table grid),
OrderDetailPage (full actions), ProductsPage (CRUD + printer zone),
WaitersPage (block/reset PIN/delete), TablesPage, ReportsPage
(shift summary + order history + CSV export), SettingsPage (printers
+ test print + sysadmin lock/unlock). TailwindCSS, React Query,
react-hot-toast. Docker Compose service on port 5174.

docker-compose.yml

@@ -26,3 +26,17 @@ services:
     depends_on:
       - backend
     restart: unless-stopped
+
+  manager_dashboard:
+    image: node:20-alpine
+    working_dir: /app
+    volumes:
+      - ./manager_dashboard:/app
+    ports:
+      - "5174:5174"
+    command: sh -c "npm install && npm run dev -- --host 0.0.0.0"
+    env_file:
+      - ./manager_dashboard/.env
+    depends_on:
+      - backend
+    restart: unless-stopped