Enhance authentication and database configuration

- Added `using DigitalData.Auth.Claims` to support claims handling.
- Improved EF Core DbContext comment for better clarity.
- Added logic to dynamically select connection strings based on
  `MIGRATION_TEST_MODE` or `UseDbMigration` configuration.
- Updated `AuthPolicy.Receiver` to include the `"receiver"` role.

EnvelopeGenerator.API/Program.cs

@@ -19,6 +19,7 @@ using DigitalData.Core.Abstractions.Security.Extensions;
 using EnvelopeGenerator.API.Middleware;
 using NLog.Web;
 using NLog;
+using DigitalData.Auth.Claims;
 
 var logger = LogManager.Setup().LoadConfigurationFromAppSettings().GetCurrentClassLogger();
 logger.Info("Logging initialized!");
@@ -112,7 +113,7 @@ try
     });
     builder.Services.AddOpenApi();
 
-    //AddEF Core dbcontext
+    //Add EF Core dbcontext
     var useDbMigration = Environment.GetEnvironmentVariable("MIGRATION_TEST_MODE") == true.ToString() || config.GetValue<bool>("UseDbMigration");
     var cnnStrName = useDbMigration ? "DbMigrationTest" : "Default";
     var connStr = config.GetConnectionString(cnnStrName)
@@ -183,7 +184,7 @@ try
         .AddPolicy(AuthPolicy.Sender, policy =>
             policy.RequireRole(Role.Sender))
         .AddPolicy(AuthPolicy.Receiver, policy =>
-            policy.RequireRole(Role.Receiver.Full))
+            policy.RequireRole(Role.Receiver.Full, "receiver"))
         .AddPolicy(AuthPolicy.ReceiverTFA, policy =>
             policy.RequireRole(Role.Receiver.TFA));