Adds --gpus flag to obliterate, run, and tourney commands for controlling
which GPUs to use (sets CUDA_VISIBLE_DEVICES). Works both locally and with
--remote. Models are automatically split across selected GPUs via
accelerate's device_map="auto". Also adds gpus field to remote YAML config.
Adds --remote [user@]host flag to obliterate, run, and tourney commands,
enabling execution on remote GPU nodes via SSH. Also supports a remote:
section in YAML configs. The remote runner handles SSH connectivity checks,
GPU detection, auto-installation of obliteratus, log streaming, and result
syncing back to the local machine via scp.