Make use_future take an impl FnMut + 'static, don't include router prelude when we don't need to

packages/fullstack/examples/axum-router/src/main.rs

@@ -5,7 +5,6 @@
 //! ```
 
 use dioxus::prelude::*;
-use dioxus_router::prelude::*;
 
 fn main() {
     let config = LaunchBuilder::fullstack();