[IMP]pms_rest_api: Add isDownPayment to move line datamodel

pms_api_rest/datamodels/pms_invoice_line.py

@@ -13,3 +13,4 @@ class PmsInvoiceLineInfo(Datamodel):
     discount = fields.Float(required=False, allow_none=True)
     displayType = fields.String(required=False, allow_none=True)
     saleLineId = fields.Integer(required=False, allow_none=True)
+    isDownPayment = fields.Boolean(required=False, allow_none=True)

pms_api_rest/services/pms_folio_service.py

@@ -573,6 +573,7 @@ class PmsFolioService(Component):
                                 saleLineId=move_line.folio_line_ids
                                 if move_line.folio_line_ids
                                 else None,
+                                isDownPayment=move_line.move_id._is_downpayment(),
                             )
                         )
                     move_url = (