Behind ORCA_LAYOUT_OWNER_IS_MAIN, a CLI or phone file open is applied by main as an
openEditorTab layout command, so a host with no window can open files. The window
reports each workspace's active group as an optional view fact on syncWindowGraph,
and shows main's tab once the frame that draws it arrives. Editor language
detection moves to shared so main can name a file's language.
Co-authored-by: E2E Test <e2e@test.local>