Record that a specific option was selected for a scorecard question answer. Both scorecard_question_answer_id and scorecard_question_option_id are required, and the option must belong to the same scorecard question as the answer. Use this on multi_select questions to add each selected option; for single_select an answer should have at most one row, so submit a single POST and delete-and-replace if the selection changes. The free-text portion of the answer (and its boolean_value for yes_no questions) lives on /v3/scorecard_question_answers — this endpoint only records the option link.