CoreWeave ARENA for practical workload evaluation

Introduces CoreWeave ARENA, a dedicated AI lab for practical workload evaluation. It emphasizes running actual workloads in a production-mirroring environment to assess performance, scalability, and cost. The post details the setup process using marimo-based notebooks, the two-step evaluation methodology (fundamental validation and workload-shaped tests), and the integration with Weights & Biases for experiment tracking and CoreWeave Mission Control for operational visibility. It also highlights support for Kubernetes (CKS) and Slurm on Kubernetes (SUNK) orchestration.