This PR makes the description in the callout that display general errors
in the agent panel be rendered as markdown. This allow us to pass URLs
to these error strings that will be clickable, improving the overall
interaction with them. Here's an example:
<img width="500" height="396" alt="Screenshot 2025-11-14 at 11 43@2x"
src="https://github.com/user-attachments/assets/f4fc629a-6314-4da1-8c19-b60e1a09653b"
/>
Release Notes:
- agent: Improved the interaction with errors by allowing links to be
clickable.