resolve_env_into(...) becomes resolve_env(manifest, agent) -> ResolvedEnv
(forwarded names + literals). The docker backend now owns env-file /
argv serialization and the --env-file newline check. Also drops stray
Docker references from manifest.py, pipelock.py, util.py, and trims
the duplicated command list from cli.py's docstring (usage() in
claude_bottle/cli/__init__.py is now the only listing).
Module name aligns with the others (manifest, pipelock, network,
log) — nouns/noun-y, not verb phrases. The function name now reads
naturally at the call site: resolve_env_into(manifest, agent,
env_file, args_file).