Follow-up to https://github.com/zed-industries/zed/pull/62614

<img width="1728" height="1084" alt="bad"
src="https://github.com/user-attachments/assets/5fafb9cb-38be-44ba-b8a3-a33dc10106da"
/>

Properly disable actions instead of showing odd toasts and do nothing
when invoked without the prerequisites.

Release Notes:

- N/A