feat(router): add connector_transaction_id in payments response (#1542)

crates/api_models/src/payments.rs

@@ -1392,6 +1392,10 @@ pub struct PaymentsResponse {
     /// Any user defined fields can be passed here.
     #[schema(value_type = Option<Object>, example = r#"{ "udf1": "some-value", "udf2": "some-value" }"#)]
     pub udf: Option<pii::SecretSerdeValue>,
+
+    /// A unique identifier for a payment provided by the connector
+    #[schema(value_type = Option<String>, example = "993672945374576J")]
+    pub connector_transaction_id: Option<String>,
 }
 
 #[derive(Clone, Debug, serde::Deserialize, ToSchema)]

crates/router/src/core/payments/transformers.rs

@@ -465,6 +465,7 @@ where
                         )
                         .set_ephemeral_key(ephemeral_key_option.map(ForeignFrom::foreign_from))
                         .set_udf(payment_intent.udf)
+                        .set_connector_transaction_id(payment_attempt.connector_transaction_id)
                         .to_owned(),
                 )
             }
@@ -509,6 +510,7 @@ where
             metadata: payment_intent.metadata,
             order_details: payment_intent.order_details,
             udf: payment_intent.udf,
+            connector_transaction_id: payment_attempt.connector_transaction_id,
             ..Default::default()
         }),
     });