feature: Custom Callback on Prompt/Response Error

[ONLYstcm]

I've noticed that a dialog is automatically presented whenever there's an error. I would like to prevent this default behavior and instead handle errors using a custom callback. Any guidance on how to disable the default error dialog behavior?

[csells]

this isn't a feature in the current implementation but it's a good idea. PRs greatly appreciated.

[ONLYstcm]

#38