Rewrote the `ExceptionHandlingMiddleware` class to improve structure and functionality, changing its namespace to `DigitalData.Core.Exceptions`. Updated the constructor to support a nullable logger and implemented null-conditional logging for unhandled exceptions. Added new package references in `DigitalData.Core.Exceptions.csproj` for `Microsoft.AspNetCore.Http.Abstractions` and `Microsoft.Extensions.Logging.Abstractions`. Introduced a new `DependencyInjection` class to register the middleware in the application's pipeline.
- Improved documentation in DIExtensions.cs for clarity.
- Added project reference to DigitalData.Core.Exceptions.
- Updated solution file to include DigitalData.Core.Exceptions.
- Introduced ExceptionHandlingMiddleware for global exception handling.
- Added BadRequestException and NotFoundException classes.
- Created DigitalData.Core.Exceptions project with .NET 7.0, 8.0, and 9.0 support.
