Match the docs to the shipped staged-env code: add the JailConfig root_path
field, a 'Staged env payloads' section (prepare_spawn_command writes env.sh/
launch.sh under /var/run/colibri-stage/<id>/), resolve the mdo-env-passthrough
open item, and add root_path to the external-MCP example.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>