Improve Documentation (#3795)

* Begin docs improvement

* Keep improving documentation

* Upgrade Docusarus

* Fix broken links

packages/twenty-docs/docs/start/cloud.mdx

@@ -0,0 +1,21 @@
+---
+title: Managed Cloud
+sidebar_position: 1
+sidebar_custom_props:
+  icon: TbRocket
+---
+import ThemedImage from '@theme/ThemedImage';
+import Tabs from '@theme/Tabs';
+import TabItem from '@theme/TabItem';
+
+
+The easiest way to try the app is to sign up on [app.twenty.com](https://app.twenty.com).
+
+We offer a free trial but require a credit-card to signup.
+
+If you just want to play around with a test instance you can use these credentials:
+
+```
+email: noah@demo.dev
+password: Applecar2025
+```