This pull request introduces a robust and flexible ONNX Runtime bootstrapping system, enabling runtime selection and execution provider configuration through user settings. It also improves package version management and updates solution/project structure for better maintainability.

ONNX Runtime support and configuration:

• Added a new OnnxRuntimeBootstrapper service to handle ONNX Runtime initialization, dynamic loading of native libraries, and execution provider selection based on user settings. This includes support for custom runtimes and advanced provider selection logic.
• Registered OnnxRuntimeBootstrapper and IOnnxRuntimeService as singletons in the dependency injection container, and ensured the bootstrapper is initialized during application startup. [1] [2]
• Integrated new settings for ONNX Runtime and execution provider selection into the application settings UI, allowing users to choose and configure their preferred runtime and provider, with documentation and dynamic options.

Build and dependency management improvements:

• Centralized the ONNX Runtime version in a new Directory.Build.props file, and updated Microsoft.ML.OnnxRuntime and Microsoft.ML.OnnxRuntime.Managed package references to use this version property for easier upgrades and consistency. [1] [2] [3]
• Updated StudioVersion to 1.0.4.3 in Base.props for version tracking.

Solution and project structure updates:

• Added Directory.Build.props to the solution and organized its placement in the /build/ folder for better discoverability and maintainability. [1] [2]
• Adjusted the order of ONNX Runtime props files in the solution for clarity.

These changes collectively enable advanced ONNX Runtime configuration, simplify dependency management, and improve project structure for future development.