Summary

• add a Chai fast runner with persistent per-device workers and batch manifests
• add --chai_fast to route Chai-1 through the fast worker while preserving the existing output layout
• add tests for device normalization, native batch layout, and preserved quality settings

Validation

• local: pre-commit run --files abcfold/chai1/run_chai1_fast.py abcfold/abcfold.py abcfold/argparse_utils.py tests/test_run_chai.py tests/test_argparse.py
• local: pytest tests/test_run_chai.py tests/test_run_boltz.py tests/test_argparse.py tests/test_export_rnp_calc.py tests/test_af3_to_boltz.py tests/test_boltz_output.py