Apply suggestions from code review

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

Author: maximthomas

openam-ui/openam-ui-js-sdk/README.md

@@ -51,7 +51,7 @@ Here's a basic example of how to use the SDK in a React application:
 
 ```tsx
 import React from 'react';
-import OpenAMUI from 'openam-js-sdk';
+import { OpenAMUI } from 'openam-js-sdk';
 
 const App = () => {
   return (

openam-ui/openam-ui-js-sdk/src/lib/components/DefaultCallbackElement.tsx

@@ -42,7 +42,7 @@ const DefaultCallbackElement: CallbackElement = ({ callback, setCallbackValue })
 
     const renderTextOutputCallback = (callback: Callback) => {
         const propMap = Object.fromEntries(callback.output.map((o) => [o.name, o.value]))
-        const messageType = propMap['messageType']
+        const messageType = String(propMap["messageType"] ?? "");
         const message = propMap['message'] as string
         switch (messageType) {
             case "0":