1774 extensibility v1 create an exhaustive documentation readme or dedicated section in twenty contributing doc (#16751)

As title

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packages/create-twenty-app/README.md

@@ -23,6 +23,7 @@ Create Twenty App is the official scaffolding CLI for building apps on top of [T
 - A Twenty workspace and an API key (create one at https://app.twenty.com/settings/api-webhooks)
 
 ## Quick start
+
 ```bash
 npx create-twenty-app@latest my-twenty-app
 cd my-twenty-app