Remove implicit optional dependency features (#2512)

* remove implicit optional dependency features

* switch to new features in desktop, router and signals crates

packages/router/src/history/web_scroll.rs

@@ -2,7 +2,6 @@ use gloo::render::{request_animation_frame, AnimationFrame};
 use web_sys::Window;
 
 #[derive(Clone, Copy, Debug, Default)]
-#[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
 pub(crate) struct ScrollPosition {
     pub x: f64,
     pub y: f64,

packages/router/src/router_cfg.rs

@@ -40,7 +40,6 @@ where
     }
 }
 
-#[cfg(not(feature = "serde"))]
 impl<R: Routable + Clone> RouterConfig<R>
 where
     <R as std::str::FromStr>::Err: std::fmt::Display,