[FEATURE] Langwatch Guardrails implementation

[4rr0wx]

Describe the feature you'd like Flowise recently added LangWatch for Chatflow analysis. LangWatch includes a feature for automatic evaluations with the ability to create guardrails. It would be beneficial to add functionality such that if a guardrail is triggered, the response is not sent to the user. Instead, a customizable error message explaining why is displayed.