- Add GetAsync_Returns404_MapsToNotFound test
- Add GetAsync_Returns400_WithValidationErrors_MapsToValidationError test
- Add GetAsync_Returns401_MapsToUnauthorized test
- Add GetAsync_Returns403_MapsToForbidden test
- Add GetAsync_Returns500_MapsToApiError test
- Add FrameworkReference to Microsoft.AspNetCore.App for ValidationProblemDetails
Set up repository with legacy .NET Framework 4.8 source (OLD/),
new .NET 10 Blazor solution (NEW/), OpenSpec specifications,
documentation, and project configuration.