New "DIV.ROC" option corporate action activity sub-type

Broker API

Adds DIV.ROC (Return of Capital) to the OPCA option corporate action sub-types on the ActivitySubType schema.

• Activity feeds can now return DIV.ROC as an activity_sub_type for option corporate actions.
• The option cash dividend activity schema now covers both cash dividend and return of capital events.

Affected Endpoints

• GET /v1/accounts/activities
• GET /v1/accounts/activities/{activity_type}
• GET /v2beta1/accounts/{account_id}/events/activities/{event_id}
• GET /v2beta1/events/activities