Module ref_fields 

The set of property names that hold component references.

Rust has no runtime catalog schema (unlike Python, which derives these from JSON Schema via CatalogSchemaValidator.extract_ref_fields()). We hardcode the a2ui-standard reference fields here:

• child (single), activeTab (single)
• children (list: either a Static array of ids, or a Template {componentId, path} whose componentId is a component reference).

This matches what ComponentModel::child() / children() already look at, and what the v0.9-flat samples use.

Structs

RefFieldSpec

Specification of which property keys carry component references.