The four raw values in the sources ladder shipped because nothing checks
the catalogues against the enum they render. The new guard reads
MeasurementSource and IntakeSource out of prisma/schema.prisma, not out
of a copy, and fails naming every member no catalogue labels; it also
asserts the key each entry names resolves in all seven bundles, since a
key that resolves nowhere renders no better than the enum value. Run red
against the tree before the labels landed, it reported seven unlabelled
measurement sources per catalogue and one unlabelled intake source.
The schema reader now carries each enum's declared members so the guard
can read them.
