New observability features: activity logging, LLM metrics, and metrics dashboard customization

We've added three new observability features to Baseten: activity logging, LLM metrics, and customizable metric views. These enhancements aim to simplify monitoring and debugging of production AI workloads by providing timestamped records, request-level metrics for LLMs, and a unified, customizable dashboard view. This allows developers to quickly identify performance issues, optimize resource allocation, and maintain the reliability required for mission-critical AI applications.