Don't render the active client app screen until the router is loaded to avoid a wasted render

packages/client/src/components/Screen.svelte

@@ -20,8 +20,10 @@
 </script>
 
 <!-- Ensure to fully remount when screen changes -->
-{#key screenDefinition?._id}
+{#if $routeStore.routerLoaded}
+  {#key screenDefinition?._id}
     <Provider key="url" data={params}>
       <Component isScreen instance={screenDefinition} />
     </Provider>
-{/key}
+  {/key}
+{/if}