after rebasing onto main, get_engine_args() loads a vllm-style config via PyYAML (a transitive vllm dep). vllm is stubbed in tests, so add pyyaml explicitly and point VLLM_CONFIG_FILE at a nonexistent path so no stray config is picked up.
after rebasing onto main, get_engine_args() loads a vllm-style config via PyYAML (a transitive vllm dep). vllm is stubbed in tests, so add pyyaml explicitly and point VLLM_CONFIG_FILE at a nonexistent path so no stray config is picked up.