Update notification logic and version numbers

Revised FinalizeEnvelopeCommand to notify each receiver
individually instead of converting documents to Base64.
Adjusted IsActive method in EnvelopeStatusExtensions to
include EnvelopePartlySigned as active. Updated project
version to 1.7.0-beta to reflect these changes.

EnvelopeGenerator.Application/PdfSigning/FinalizeEnvelopeCommand.cs

@@ -91,7 +91,7 @@ public class FinalizeEnvelopeCommandHandler(IRepository<Envelope> Repo, ISender
         using var ms = new MemoryStream();
         docStream.CopyTo(ms);
         byte[] doc = ms.ToArray();
-        string base64 = Convert.ToBase64String(doc);
+
         foreach (var er in envelope.EnvelopeReceivers)
         {
             await NtfServer.Notify(er.Receiver.EmailAddress, new DocumentSignedNotification()