codify "platform" into resolution logic, server-fn/fullstack overhaul (#4596)

overhaul dioxus fullstack using a new implementation of server_fn

This PR is a complete rewrite of dioxus fullstack designed to improve compatibility with axum and to fix a number of compilation errors based on feature flag unification plumbing through macros.

examples/06-routing/simple_router.rs

@@ -0,0 +1,68 @@
+//! A simple example of a router with a few routes and a nav bar.
+
+use dioxus::prelude::*;
+
+fn main() {
+    // launch the router, using our `Route` component as the generic type
+    // This will automatically boot the app to "/" unless otherwise specified
+    dioxus::launch(|| rsx! { Router::<Route> {} });
+}
+
+/// By default, the Routable derive will use the name of the variant as the route
+/// You can also specify a specific component by adding the Component name to the `#[route]` attribute
+#[rustfmt::skip]
+#[derive(Routable, Clone, PartialEq)]
+enum Route {
+    // Wrap the app in a Nav layout
+    #[layout(Nav)]
+        #[route("/")]
+        Homepage {},
+
+        #[route("/blog/:id")]
+        Blog { id: String },
+}
+
+#[component]
+fn Homepage() -> Element {
+    rsx! { h1 { "Welcome home" } }
+}
+
+#[component]
+fn Blog(id: String) -> Element {
+    rsx! {
+        h1 { "How to make: " }
+        p { "{id}" }
+    }
+}
+
+/// A simple nav bar that links to the homepage and blog pages
+///
+/// The `Route` enum gives up typesafe routes, allowing us to rename routes and serialize them automatically
+#[component]
+fn Nav() -> Element {
+    rsx! {
+        nav {
+            li {
+                Link { to: Route::Homepage {}, "Go home" }
+            }
+            li {
+                Link {
+                    to: Route::Blog {
+                        id: "Brownies".to_string(),
+                    },
+                    onclick: move |_| { println!("Clicked on Brownies") },
+                    "Learn Brownies"
+                }
+            }
+            li {
+                Link {
+                    to: Route::Blog {
+                        id: "Cookies".to_string(),
+                    },
+                    "Learn Cookies"
+                }
+            }
+        }
+        div { Outlet::<Route> {} }
+    }
+}