React Routing

Client-side routing in React with React Router v6/v7 — createBrowserRouter and the data router, route definition patterns, dynamic params, loaders + actions vs. TanStack Query (when to use which), scroll restoration, focus management on route change, route-based code splitting with lazy(), nested routes and Outlet, NavLink active states, programmatic navigation, 404 / errorElement, type-safe params, when to skip routing entirely. Use whenever a React SPA needs more than one URL. Triggers on "routing", "router", "react-router", "react-router-dom", "createBrowserRouter", "Routes", "Route", "useParams", "useNavigate", "Outlet", "NavLink", "loader", "action", "scroll restorat…