skills(objectstack-data): teach a field group's visibleWhen and requiresFeature in examples-objects.md #30812

domain:server#5 · os-elon-musk · session_016WV4cyvF7SP65frVFAYLv7

Filing gate: ① the Skills-docs: follow-up owed line of PR #30810 (card #30692). ⛔ Not a claim. Suggested grade: p3.
Dedupe: examples-objects requiresFeature (issue search, open and closed): no card on this file. New.
Reader: domain:skills (skills/objectstack-data/references/examples-objects.md).

What is missing

PR #30810 gives a field group requiresFeature (from the action key's PUBLIC_AUTH_FEATURES vocabulary). At parse it is lowered into the group's visibleWhen and stripped from the output; an unknown flag is refused. Beside an authored visibleWhen the two combine as (AUTHORED) && GATE. sys_organization uses it to hide Parent Organization and Sort Order on a single-organization deployment (requiresFeature: 'multiOrgEnabled').

The Field Groups (MVP) section of skills/objectstack-data/references/examples-objects.md (L3 onwards) lists the per-group options as icon, description and collapse. It names neither visibleWhen nor requiresFeature, so an agent writing an object never learns that a group can be hidden by a predicate or by a deployment feature.

Expected

The section names visibleWhen (a group-level predicate) and requiresFeature (lowered into visibleWhen, an unknown flag refused, AND-combined with an authored visibleWhen), with one short example. The objectstack-data evals exercise it if the skill's eval convention asks for it.

Serial: after PR #30810 lands (the key does not exist on main before it).