62d2e36e5c
Previously prepare wrote two on-disk artifacts that launch consumed: agent.env (NAME=VALUE) and docker-args (paired -e\nNAME\n lines), with launch parsing the second back into argv. Docker requires the literals file on disk for --env-file, but the args-file round-trip was a pure serialize/deserialize trip with hand-rolled line pairing logic. Drop docker-args entirely. Pass forwarded names as a structured tuple[str, ...] field on DockerBottlePlan; launch iterates it directly to extend docker_args. _write_env_files becomes _write_env_file (only the literals file remains).