Closes https://github.com/zed-industries/zed/issues/61112

Now behaves similar to VSCode: 

<img width="857" height="552" alt="1"
src="https://github.com/user-attachments/assets/bed95600-c75c-4b1d-a750-17b9eb35db92"
/>

<img width="601" height="243" alt="2"
src="https://github.com/user-attachments/assets/b2e839a5-6ca3-4e3a-8e5f-bc8b3e9a565f"
/>

Release Notes:

- Fixed rust-analyzer's macro with nested tabstops causing panics when
completed