Add Swiss QR Code extraction endpoint

Added a new `/extract-swiss-qr-code` endpoint to extract and parse Swiss QR Codes from the last page of a PDF document. Implemented the `ExtractSwissQrCode` handler method, along with helper methods to map domain value objects (`SwissQrCodeData` and `AddressData`) to DTOs.

Updated `ExceptionHandlingMiddleware` to handle the new `SwissQrCodeNotFoundException` with a 404 Not Found response.

Added integration tests in `ExtractSwissQrCodeEndpointTests` to validate the endpoint's behavior for valid requests, invalid Base64 input, empty references, and empty PDFs. Introduced a helper method to load embedded PDF resources as Base64 strings for testing.

Updated `using` directives to include necessary namespaces for the new feature and exception handling.

DocumentOperator.API/Endpoints/v1/DocumentEndpoints.cs

@@ -1,4 +1,5 @@
 using DocumentOperator.Application.Common.DTOs;
+using DocumentOperator.Application.Features.Documents.ExtractSwissQrCode;
 using DocumentOperator.Application.Features.Documents.ValidatePdf;
 using DocumentOperator.Domain.Models.ValueObjects;
 using MediatR;
@@ -27,6 +28,16 @@ public static class DocumentEndpoints
             .Produces<ValidatePdfResponse>(StatusCodes.Status200OK)
             .Produces<ProblemDetails>(StatusCodes.Status400BadRequest)
             .Produces<ProblemDetails>(StatusCodes.Status500InternalServerError);
+
+        // POST /api/v1/documents/extract-swiss-qr-code
+        group.MapPost("/extract-swiss-qr-code", ExtractSwissQrCode)
+            .WithName("ExtractSwissQrCode")
+            .WithSummary("Extracts Swiss QR Code from the last page of a PDF document")
+            .WithDescription("Extracts and parses a Swiss QR Code (Swiss QR Bill Standard 2.0) from the last page of a PDF. Returns references (passed through) and all QR code fields.")
+            .Produces<ExtractSwissQrCodeResponse>(StatusCodes.Status200OK)
+            .Produces<ProblemDetails>(StatusCodes.Status400BadRequest)
+            .Produces<ProblemDetails>(StatusCodes.Status404NotFound)
+            .Produces<ProblemDetails>(StatusCodes.Status500InternalServerError);
     }
 
     /// <summary>
@@ -64,4 +75,79 @@ public static class DocumentEndpoints
 
         return Results.Ok(response);
     }
+
+    /// <summary>
+    /// Extracts Swiss QR Code from the last page of a PDF document
+    /// </summary>
+    /// <param name="request">References array + PDF as Base64 string</param>
+    /// <param name="mediator">MediatR instance</param>
+    /// <param name="cancellationToken">Cancellation token</param>
+    /// <returns>References (passed through) + Swiss QR Code data</returns>
+    /// <response code="200">Swiss QR Code extracted successfully</response>
+    /// <response code="400">Invalid PDF or Base64 format</response>
+    /// <response code="404">No Swiss QR Code found on the last page</response>
+    /// <response code="500">Internal server error during extraction</response>
+    private static async Task<IResult> ExtractSwissQrCode(
+        ExtractSwissQrCodeRequest request,
+        IMediator mediator,
+        CancellationToken cancellationToken)
+    {
+        // DTO → Query (Value Objects erstellen)
+        var query = new ExtractSwissQrCodeQuery(
+            References: request.References,
+            PdfContent: Base64String.Create(request.Base64Pdf)
+        );
+
+        // MediatR Handler aufrufen
+        var result = await mediator.Send(query, cancellationToken);
+
+        // Map Domain Value Object → DTO
+        var response = new ExtractSwissQrCodeResponse(
+            References: result.References,
+            QrCodeData: MapQrCodeDataToDto(result.QrCodeData)
+        );
+
+        return Results.Ok(response);
+    }
+
+    /// <summary>
+    /// Maps SwissQrCodeData domain value object to DTO
+    /// </summary>
+    private static SwissQrCodeDataDto MapQrCodeDataToDto(Domain.ValueObjects.SwissQrCodeData qrCodeData)
+    {
+        return new SwissQrCodeDataDto(
+            QrType: qrCodeData.QrType,
+            Version: qrCodeData.Version,
+            CodingType: qrCodeData.CodingType,
+            Iban: qrCodeData.Iban,
+            Creditor: MapAddressToDto(qrCodeData.Creditor),
+            UltimateCreditor: qrCodeData.UltimateCreditor != null ? MapAddressToDto(qrCodeData.UltimateCreditor) : null,
+            Amount: qrCodeData.Amount,
+            Currency: qrCodeData.Currency,
+            UltimateDebtor: qrCodeData.UltimateDebtor != null ? MapAddressToDto(qrCodeData.UltimateDebtor) : null,
+            ReferenceType: qrCodeData.ReferenceType,
+            Reference: qrCodeData.Reference,
+            UnstructuredMessage: qrCodeData.UnstructuredMessage,
+            BillInformation: qrCodeData.BillInformation,
+            AlternativeProcedureParameters: qrCodeData.AlternativeProcedureParameters
+        );
+    }
+
+    /// <summary>
+    /// Maps AddressData domain value object to DTO
+    /// </summary>
+    private static AddressDataDto MapAddressToDto(Domain.ValueObjects.AddressData address)
+    {
+        return new AddressDataDto(
+            AddressType: address.AddressType,
+            Name: address.Name,
+            Street: address.Street,
+            BuildingNumber: address.BuildingNumber,
+            AddressLine1: address.AddressLine1,
+            AddressLine2: address.AddressLine2,
+            PostalCode: address.PostalCode,
+            City: address.City,
+            Country: address.Country
+        );
+    }
 }