Create twenty app improvements (#20688)

create-twenty-app updates:
- remove --example option
- sync --once when scaffolding an applicaiton
- rename --api-url option to --workspace-url
- create a standalone page when scaffolding an app
<img width="1494" height="765" alt="image"
src="https://github.com/user-attachments/assets/0e35ed0c-b0aa-466c-9f56-7939294fd2cf"
/>

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packages/create-twenty-app/src/utils/docker-install.ts

@@ -28,6 +28,6 @@ export const getDockerInstallInstructions = (): string => {
     '  Then run this command again.',
     '',
     '  Alternatively, connect to an existing Twenty instance:',
-    '  npx create-twenty-app@latest my-twenty-app --api-url <your-instance-url>',
+    '  npx create-twenty-app@latest my-twenty-app --workspace-url <your-instance-url>',
   ].join('\n');
 };