Refactor SQL queries and data mappings

- Updated SQL query in `EnvelopeReceiverAddReadSQL.cs` to select specific columns (`ENVELOPE_ID` and `RECEIVER_ID`) for improved performance and clarity.
- Changed mapping of `SentRecipients` in `EnvelopeReceiverController.cs` to expect a single `ReceiverReadDto` instead of a collection, reflecting a change in data handling.
- Modified `QueryAsync` in `EnvelopeReceiverExecutor.cs` to remove the generic type parameter, allowing for more flexible data handling.

EnvelopeGenerator.Application/SQL/EnvelopeReceiverAddReadSQL.cs

@@ -22,8 +22,8 @@ public class EnvelopeReceiverAddReadSQL : ISQL<Envelope>
 				{3},
 				@OUT_RECEIVER_ID OUTPUT
 
-		SELECT TOP(1) *
-		FROM TBSIG_ENVELOPE_RECEIVER
+        SELECT TOP(1) [ENVELOPE_ID] As EnvelopeId, [RECEIVER_ID] As ReceiverId
+        FROM [dbo].[TBSIG_ENVELOPE_RECEIVER]
 		WHERE [GUID] = @OUT_RECEIVER_ID;
 	";