"foreign" and "special" on dividend activities are JSON strings

Broker API

The foreign and special fields on dividend activity details are serialized as the JSON strings "true" or "false", not JSON booleans. The descriptions on the CommonCDIVActivityV2 and DIVSPDActivityV2 schemas now state this explicitly and include a "false" example.

The wire format is unchanged; only the documentation is clarified.

Affected Endpoints

• GET /v2beta1/events/activities
• GET /v2beta1/accounts/{account_id}/events/activities/{event_id}