more fullstack cleanups: loaders serialize, ServeConfig only (#4785)

* some opinionated cleanups in dioxus-server

* add serialize to loader

* add `result` to Resource

* clippy

* fix

* writable memos, resources, `onmount`, `.pending`, and `.value()` on actions

* fix compile issues

* fix typo

examples/05-using-async/suspense.rs

@@ -43,8 +43,7 @@ fn Doggo() -> Element {
         }
 
         reqwest::get("https://dog.ceo/api/breeds/image/random/")
-            .await
-            .unwrap()
+            .await?
             .json::<DogApi>()
             .await
     })?;