test: Update tests for tuple return type and new API structure

- Update unit tests to assert (Bill, string[]) tuple return
- Update integration tests for new response structure (Bill + RawLines)
- Fix exception message assertion in DevExpressSwissQrCodeProcessorTests
- All 34 tests passing, 6 skipped (require real Swiss QR Bill PDFs)

DocumentOperator.Tests/Integration/API/ExtractSwissQrCodeEndpointTests.cs

@@ -31,7 +31,6 @@ public sealed class ExtractSwissQrCodeEndpointTests : IClassFixture<WebApplicati
 
         var request = new ExtractSwissQrCodeQuery
         {
-            References = new List<string> { "REF-001", "REF-002" },
             Base64Pdf = validPdfBase64
         };
 
@@ -48,8 +47,8 @@ public sealed class ExtractSwissQrCodeEndpointTests : IClassFixture<WebApplicati
         {
             var result = await response.Content.ReadFromJsonAsync<SwissQrCodeExtractionResult>(_jsonOptions);
             result.Should().NotBeNull();
-            result!.References.Should().BeEquivalentTo(new[] { "REF-001", "REF-002" });
-            result.QrCodeData.Should().NotBeNull();
+            result.Bill.Should().NotBeNull();
+            result.RawLines.Should().NotBeEmpty();
         }
     }
 
@@ -59,7 +58,6 @@ public sealed class ExtractSwissQrCodeEndpointTests : IClassFixture<WebApplicati
         // Arrange
         var request = new ExtractSwissQrCodeQuery
         {
-            References = new List<string> { "REF-001" },
             Base64Pdf = "INVALID_BASE64!!!"
         };
 
@@ -95,7 +93,6 @@ public sealed class ExtractSwissQrCodeEndpointTests : IClassFixture<WebApplicati
         {
             var result = await response.Content.ReadFromJsonAsync<SwissQrCodeExtractionResult>();
             result.Should().NotBeNull();
-            result!.References.Should().BeEmpty(); // Null input → empty output array
         }
     }