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/08-apis/window_focus.rs

@@ -0,0 +1,39 @@
+//! Listen for window focus events using a wry event handler
+//!
+//! This example shows how to use the use_wry_event_handler hook to listen for window focus events.
+//! We can intercept any Wry event, but in this case we're only interested in the WindowEvent::Focused event.
+//!
+//! This lets you do things like backgrounding tasks, pausing animations, or changing the UI when the window is focused or not.
+
+use dioxus::desktop::tao::event::Event as WryEvent;
+use dioxus::desktop::tao::event::WindowEvent;
+use dioxus::desktop::use_wry_event_handler;
+use dioxus::prelude::*;
+
+fn main() {
+    dioxus::launch(app);
+}
+
+fn app() -> Element {
+    let mut focused = use_signal(|| true);
+
+    use_wry_event_handler(move |event, _| {
+        if let WryEvent::WindowEvent {
+            event: WindowEvent::Focused(new_focused),
+            ..
+        } = event
+        {
+            focused.set(*new_focused)
+        }
+    });
+
+    rsx! {
+        div { width: "100%", height: "100%", display: "flex", flex_direction: "column", align_items: "center",
+            if focused() {
+                "This window is focused!"
+            } else {
+                "This window is not focused!"
+            }
+        }
+    }
+}