How to force terminal mode?

I noticed in this screenshot in this tweet Claude CLI is run full screen. I can't find a way to run Claude CLI in such full screen tab way, I only see how to launch chat mode. Can someone help figuring out? Thanks. https://x.com/theo/status/2054618101615047029
<img width="3600" height="2260" alt="Image" src="https://github.com/user-attachments/assets/b075c35e-acf9-4c79-b25d-d2e931cfbaf9" />