AWS PCS now supports custom GRES, hardware topology, and MIG

Summary

• AWS PCS adds custom GRES configuration, hardware topology support, and upgrades to Slurm 26.05.
• Enables NVIDIA MIG GPU partitioning with automatic GPU core affinity and inter‑GPU interconnect detection for better MPI and GPU job placement.
• Provides default NUMA‑to‑socket mapping and allows overriding defaults for accelerators, L3 cache domains, and other resources.