Returns beneficiaries (typically loan_client type) that belong to the given organisation. Requires internal-admin or org-admin role.
Supports an optional query search parameter and DynamoDB cursor pagination via next_token (a JSON-encoded key passed as a query string).
Filter by beneficiary_type (e.g. loan_client, payout_recipient).
loan_client, payout_recipient Free-text search string applied by the use-case layer.
JSON-encoded DynamoDB pagination token from a previous response.