Improve doc of payment requests

BTCPayServer.Client/Models/PaymentRequestBaseData.cs

@@ -9,9 +9,21 @@ namespace BTCPayServer.Client.Models
 {
     public enum PaymentRequestStatus
     {
+        /// <summary>
+        /// Not enough has been paid or settled
+        /// </summary>
         Pending,
+        /// <summary>
+        /// Paid and fully settled
+        /// </summary>
         Completed,
+        /// <summary>
+        /// Expired before full settlement
+        /// </summary>
         Expired,
+        /// <summary>
+        /// Paid enough, awaiting full settlement
+        /// </summary>
         Processing,
     }
     public class PaymentRequestBaseData

BTCPayServer/wwwroot/swagger/v1/swagger.template.payment-requests.json

@@ -396,9 +396,10 @@
                                 "enum": [
                                     "Pending",
                                     "Completed",
+                                    "Processing",
                                     "Expired"
                                 ],
-                                "description": "The status of the payment request",
+                                "description": "Represents the status of a payment request:\n* `Pending`: Not enough has been paid or settled.\n* `Completed`: Paid and fully settled.\n* `Expired`: Expired before full settlement.\n* `Processing`: Paid enough, awaiting full settlement.",
                                 "nullable": false
                             },
                             "createdTime": {