Introducing End-to-End OpenTelemetry Support in LangSmith

LangSmith now provides full end-to-end OpenTelemetry (OTel) support for applications developed with LangChain and LangGraph. This update allows for standardized tracing across the entire application stack, enabling a unified view of system behavior and performance. The integration facilitates distributed tracing and interoperability with other observability tools, allowing developers to connect LangSmith with platforms like Datadog or Grafana. While the OTel support offers greater flexibility, the native LangSmith tracing format is still recommended for optimal performance when used exclusively with the platform.