Sound on error

Actually TypingMind plays a sound when LLM answers but not when LLM doesn’t answer (eg: overloaded).

TypingMind should play an error sound also when the answer is like “Sorry, the provider of this model has rejected your request (Message: This model is currently experiencing high demand. Spikes in demand are usually temporary. Please try again later.). Please try again or contact support.” or else it will be hard to know about the error if the TypingMind user is not watching the UI.