CHW-4327 FindingFeedbackInvalidAction

feedback action must be one of: false_positive, true_positive, retract; retract requires a referencing_event_id

Default message: feedback action must be one of: false_positive, true_positive, retract; retract requires a referencing_event_id
HTTP status: 400 (client)

Problem. POST /api/findings/{id}/feedback was rejected with 400. Cause. The action field is outside the accepted set (false_positive, true_positive, retract), or retract was sent without a referencing event_id. Fix. Send a valid action; for retract, include the event_id of the prior feedback being retracted. HTTP 400.