feat(RemoveSignatureNotification): add validation and filter logic to RemoveSignatureNotification

- Added `HasFilter` property to check if any filter parameters are provided.
- Implemented `ThrowIfHasNoFilter()` method to enforce at least one filter parameter.
- Improves robustness and validation of RemoveSignatureNotification.

EnvelopeGenerator.Application/Common/Notifications/RemoveSignature/RemoveSignatureNotification.cs

@@ -14,4 +14,24 @@ public record RemoveSignatureNotification(
     int? ReceiverId = null,
     string? EnvelopeUuid = null,
     string? ReceiverSignature = null
-    ) : INotification;
+    ) : INotification
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    public bool HasFilter => 
+        EnvelopeId is not null 
+        || ReceiverId is not null 
+        || EnvelopeUuid is not null 
+        || ReceiverSignature is not null;
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <exception cref="InvalidOperationException"></exception>
+    public void ThrowIfHasNoFilter()
+    {
+        if (!HasFilter)
+            throw new InvalidOperationException("At least one filter parameter must be provided.");
+    }
+}