feat: add admin risk actions and arbitration settlement

backend/internal/modules/listing/dto.go

@@ -56,3 +56,12 @@ type AdminListQuery struct {
 	ReviewStatus string
 	Limit        int
 }
+
+type AdminActionRequest struct {
+	Reason string `json:"reason" binding:"required"`
+}
+
+type AuditMeta struct {
+	IP        string
+	UserAgent string
+}