Add optional project_id param to run_home_stream. When set, fetch the linked
folder manifest via _fetch_project_manifest and prepend the <linked_folder>
block to the system prompt. Also build an explicit tools list that extends
_all_tools_for_user with FOLDER_TOOLS so the home agent can read folder
files. device_ws._handle_home_request extracts project_id / projectId from
the home_request frame and forwards it to the runner.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>