Atlas org map — the groups lane (PR #16014)

The admin org map, rendered from the real OrgMapView component over the bench fixture (benchAtlasData() + benchOrgGroups()), server-rendered and screenshotted headless. No customer data: the fixture is synthetic. Prod has no groups today, so nothing here appears in prod yet.

• North Chain — a chain group (walked by the resolver): solid edges to Alder One and Alder Two. Its third membership (Alder Three) ended, so no edge.
• Group grp_ghost — a membership whose group profile can't be read: drawn by id, badged no readable profile, edge dashed (kind unknown, never drawn as walked).
• Alder One — also sits in another company's group: never an edge across companies, only the gap chip in another company's group · grp_other.
• Known limit, from the review: middle-lane cards share one bus line, so North Chain's solid bus runs on top of the company's bus. The sublabel, the table and the text dump say which buildings each group holds.