chore: fix route matching priority example - #3889

The current "Route matching priority" example is a bit confusing because the inline comments contradict the preceding explanation
The documentation states that:
1. Static routes are always checked first.
2. Dynamic routes are checked in registration order.
However, the example comments imply that `/posts/featured` is matched first because it was registered first, rather than because it is a static route.
This PR updates the example to:
- demonstrate that registration order only affects dynamic routes;
- clarify that static routes always take precedence regardless of registration order.