Spawn the local `claude` binary as a subprocess and expose it as an
Anthropic Messages-compatible provider. Hosted in brightstaff
(`CLAUDE_CLI_LISTEN_ADDR`), with session reuse, idle TTL, and watchdog.
User-facing surface is `model_providers: [{ model: claude-cli/* }]` —
the Python CLI auto-fills name/provider_interface/base_url/access_key
and the launcher (native + supervisord) enables the bridge listener
only when at least one claude-cli provider is present.
