docs: remove all usages of static closure syntax and update readme

examples/tasks.rs

@@ -12,13 +12,14 @@ fn main() {
 fn app(cx: Scope) -> Element {
     let count = use_state(&cx, || 0);
 
-    use_future(&cx, || {
-        for_async![count];
+    use_future(&cx, move || {
+        let count = UseState::for_async(&count);
+        // for_async![count];
         async move {
-            loop {
-                tokio::time::sleep(Duration::from_millis(1000)).await;
-                count += 1;
-            }
+            // loop {
+            //     tokio::time::sleep(Duration::from_millis(1000)).await;
+            //     count += 1;
+            // }
         }
     });