fix: resolve test failures from timezone conversion and interface rename

- Fix CriteriaSheetGenerator.FormatTimestamp to handle all DateTimeKind values
- Update TestWebApplicationFactory to use IAuthenticationService
- Add logger parameter to ExcelParserServiceTests
- Add SecureStoreManager to solution under /utils/ folder

NEW/tests/JdeScoping.SecureStoreManager.Tests/TestAppBuilder.cs

@@ -0,0 +1,14 @@
+using Avalonia;
+using Avalonia.Headless;
+using JdeScoping.SecureStoreManager;
+
+[assembly: AvaloniaTestApplication(typeof(JdeScoping.SecureStoreManager.Tests.TestAppBuilder))]
+
+namespace JdeScoping.SecureStoreManager.Tests;
+
+public class TestAppBuilder
+{
+    public static AppBuilder BuildAvaloniaApp() =>
+        AppBuilder.Configure<App>()
+            .UseHeadless(new AvaloniaHeadlessPlatformOptions());
+}