translatable property
True only on a dotted leaf (caption.ar) whose head attribute
(caption) is translatable on the model — the writable/placeholder
precedent: published only when true, absent everywhere else, including
the undotted scalar sibling. The form screen groups every leaf sharing
a head-of-name into one field slot with locale chips instead of one
stacked field per locale; see ResourceFormScreen's node walk.
Implementation
final bool translatable;