Remove EnvelopeModel class and its GetById method

Deleted the EnvelopeModel class, which included the GetById method for retrieving Envelope entities from the database. Also removed related using directives and namespace declarations. This cleanup eliminates unused or redundant code.

EnvelopeGenerator.ServiceHost/Jobs/EnvelopeModel.cs

@@ -1,38 +0,0 @@
-using DigitalData.Modules.Database;
-using EnvelopeGenerator.Domain.Entities;
-using EnvelopeGenerator.ServiceHost.Extensions;
-
-namespace EnvelopeGenerator.ServiceHost.Jobs;
-
-public class EnvelopeModel(MSSQLServer Database, ILogger Logger)
-{
-    public Envelope? GetById(int envelopeId)
-    {
-        try
-        {
-            var sql = $"SELECT * FROM [dbo].[TBSIG_ENVELOPE] WHERE GUID = {envelopeId}";
-            var table = Database.GetDatatable(sql);
-            var row = table.Rows.Cast<System.Data.DataRow>().SingleOrDefault();
-            if (row is null)
-            {
-                return null;
-            }
-
-            return new Envelope
-            {
-                Id = row.ItemEx("GUID", 0),
-                Uuid = row.ItemEx("ENVELOPE_UUID", string.Empty),
-                FinalEmailToCreator = row.ItemEx("FINAL_EMAIL_TO_CREATOR", 0),
-                FinalEmailToReceivers = row.ItemEx("FINAL_EMAIL_TO_RECEIVERS", 0),
-                UserId = row.ItemEx("USER_ID", 0),
-                User = null!,
-                EnvelopeReceivers = new List<EnvelopeReceiver>()
-            };
-        }
-        catch (Exception ex)
-        {
-            Logger.LogError(ex);
-            return null;
-        }
-    }
-}