Retired in favor of Eidoverse. The retired OpenWorld implementation was removed. Persistent
/openworld,/openworld/*,/city, and/city/*URLs redirect to/eidoversewithout retaining deep-path suffixes.
Existing data/city-snapshots.jsonl files remain untouched and inert. Eidoverse is the canonical optional 3D surface.
Historical rename (2026-08-19). This surface originally shipped as CyberCity at
/city, then as OpenWorld at/openworld. The permanent redirects preserve bookmarks, pinned rows, and command-palette history.