Enhance JSON options and authorization policies

Added JSON serialization options to ignore reference cycles in
the `AddControllers` method by configuring `ReferenceHandler`
to `IgnoreCycles`. Updated the `AddAuthorizationBuilder` to
include authentication schemes for the `SenderOrReceiver`
policy, requiring roles and schemes for enhanced security.

EnvelopeGenerator.API/Program.cs

@@ -44,7 +44,11 @@ try
 
     var deferredProvider = new DeferredServiceProvider();
 
-    builder.Services.AddControllers();
+    builder.Services.AddControllers()
+        .AddJsonOptions(options =>
+        {
+            options.JsonSerializerOptions.ReferenceHandler = System.Text.Json.Serialization.ReferenceHandler.IgnoreCycles;
+        });
     builder.Services.AddHttpClient();
     builder.Services.AddReverseProxy().LoadFromConfig(builder.Configuration.GetSection("ReverseProxy"));
 
@@ -238,8 +242,9 @@ try
     });
 
     builder.Services.AddAuthorizationBuilder()
-        .AddPolicy(AuthPolicy.SenderOrReceiver, policy => policy.RequireRole(Role.Sender, Role.Receiver.Full))
-
+        .AddPolicy(AuthPolicy.SenderOrReceiver, policy => policy
+            .RequireRole(Role.Sender, Role.Receiver.Full)
+            .AddAuthenticationSchemes(AuthScheme.Sender, AuthScheme.Receiver))
         .AddPolicy(AuthPolicy.Sender, policy => policy
             .RequireRole(Role.Sender)
             .AddAuthenticationSchemes(AuthScheme.Sender))