fix: state updates detection on back/forward event

Author: oedotme

src/routing.ts

@@ -7,6 +7,7 @@ import {
   createSignal,
   on,
   onCleanup,
+  onMount,
   untrack,
   useContext,
   startTransition,
@@ -326,6 +327,10 @@ export function createRouterContext(
     }
   };
 
+  const handlePopState = () => setState(window.history.state);
+  onMount(() => window.addEventListener("popstate", handlePopState));
+  onCleanup(() => window.removeEventListener("popstate", handlePopState));
+
   createRenderEffect(() => {
     const { value, state } = source();
     // Untrack this whole block so `start` doesn't cause Solid's Listener to be preserved