zeta: Respect `x-zed-minimum-required-version` header (#24771)

This PR makes it so Zeta respects the `x-zed-minimum-required-version`
header sent back from the server.

If the current Zed version is strictly less than the indicated minimum
required version, we show an error indicating that an update is required
in order to continue using Zeta:

<img width="472" alt="Screenshot 2025-02-12 at 6 15 44 PM"
src="https://github.com/user-attachments/assets/51b85dff-23a0-464c-ae4b-5b8f46b5915c"
/>

Release Notes:

- N/A