CountryDto: nationalityAllowed maps to an unused column; no DTO field exposes the real nationality gate

[TaprootFreak]

Problem

CountryDto exposes allow-flags that are derived aliases in country-dto.mapper.ts, and one alias is misleading:

• nationalityAllowed is mapped from the entity column nationalityStepEnable.
• nationalityStepEnable is read nowhere in the backend (only defined on the entity and used in this mapper).
• The actual nationality validation uses a different column, nationalityEnable (kyc.service.ts, getNationalityErrors / getIdentCheckErrors).

So no CountryDto field reflects the real nationality gate. A client that filters its nationality picker by nationalityAllowed filters by a dead flag, and its UI can silently diverge from backend enforcement for any country where the two columns differ.

For reference, the correct mapping for the address/residence country is kycAllowed = dfxEnable (enforced in user-data.service.ts updatePersonalData), and locationAllowed = ipEnable gates the request IP's country, not a user-entered field.

Secondary

displayOrder is consumed by clients (e.g. realunit-app picker ordering), but no displayOrder column exists on the Country entity or in any migration — clients always receive undefined.

Suggested fix

• Fix the mapper to use nationalityEnable, or expose nationalityEnable as its own DTO field; remove nationalityAllowed if nationalityStepEnable is genuinely unused.
• Either add a real displayOrder column or stop documenting/consuming it.

Context

Found during a deep audit of the realunit-app country pickers (DFXswiss/realunit-app#519), which had to be corrected because the DTO flag names do not match enforced semantics.