OpenRegister refuses null for the required nullable LvsResult.dataExchangeJobId #1844

What is missing

OpenRegister refuses null for LvsResult.dataExchangeJobId, although the schema says null is allowed.

Why it matters

A result entered by hand has no exchange job. The property is required and nullable: true, and OpenRegister answers "should be type string but is null". So such a result cannot be saved.

Where

• lib/Settings/learniq_register.json, schema LvsResult (lvs-result), property dataExchangeJobId, listed in required.

Already done

• fix(lvs): freeze a verified LVS score now that LvsResult is no longer append-only #1195 made the field nullable, which satisfies hydra gate 101. [OpenSpec] oso-import-dossier-nullable-job #1236 does the same for OsoImportDossier.
• Seen while landing the demo set in fix(demo): the demo set lands every object in the register's own schemas, and a demo session finds its assignment #1713.

Done when

• Saving an LvsResult with dataExchangeJobId: null works, through the API on a live instance.
• Either learniq drops the field from required, or OpenRegister accepts null for a required nullable property. If the second, the fix goes to OpenRegister.