Add the ability to use custom LiveError component.

### Is there an existing issue for this?

- [x] I have searched the existing issues

### Code of Conduct

- [x] I agree to follow this project's Code of Conduct

### Feature Request

```markdown
Hi there!

I'm working on a generative UI concept powered by an LLM-based code generator, where the UI components are dynamically generated through LLM outputs.

Since the code is AI-generated, it occasionally contains errors or incomplete implementations. I'd like to integrate a custom LiveError component that can handle these errors gracefully and trigger logic to automatically re-fetch or regenerate the component code when an error occurs.

I believe this would improve the resilience of the live editing experience in LLM-driven workflows.

Would you be open to adding support for this feature? I'd be happy to contribute with a PR if you're on board!

Thanks so much for your work!
```