Less clumsy configuration for desktop and mobile (#553)

* chore: dont use prebuilt builder pattern for configuring desktop

* chore: use regular config pattern for web

* Chore: update docs too

* chore: clean up some warnings

docs/guide/examples/hooks_composed.rs

@@ -8,6 +8,6 @@ struct AppSettings {}
 
 // ANCHOR: wrap_context
 fn use_settings(cx: &ScopeState) -> UseSharedState<AppSettings> {
-    use_context::<AppSettings>(&cx).expect("App settings not provided")
+    use_context::<AppSettings>(cx).expect("App settings not provided")
 }
 // ANCHOR_END: wrap_context