feat(notification): distinguish read confirmation from signature

Add IsReadAndConfirm to DocumentSignedNotification and derive the action, status, and final action labels from it so read-only envelopes do not report a signature.

Pass the envelope read-and-confirm mode when finalizing so the signed email matches the receiver workflow.

EnvelopeGenerator.Application/PdfSigning/FinalizeEnvelopeCommand.cs

@@ -98,7 +98,8 @@ public class FinalizeEnvelopeCommandHandler(IRepository<Envelope> Repo, ISender
             {
                 DocumentTitle = envelope.Title,
                 NameReceiver = er.Name,
-                Attachments = [($"unterzeichnetes-dokument.pdf", doc)]
+                Attachments = [($"unterzeichnetes-dokument.pdf", doc)],
+                IsReadAndConfirm = envelope.IsReadAndConfirm(),
             }, cancel);
         }