RHS does not show code runnables already, and lens blocks break the
background highlights, hence remove them too.

Before:

<img width="1728" height="1084" alt="before"
src="https://github.com/user-attachments/assets/6e942568-dcbf-4624-86f6-7f3f31d01d31"
/>

After:

<img width="1728" height="1084" alt="Screenshot 2026-05-14 at 11 13 05"
src="https://github.com/user-attachments/assets/ec3bfcb9-daab-4a33-b799-db86ac352488"
/>

Release Notes:

- Removed code lens from the diff view