Enable Nullable Reference Types

[LaithSaq]

Rationale

Our codebase does not currently utilize C#'s nullable reference type system, which increases the risk of encountering NullReferenceExceptions at runtime. Enabling this feature allows the C# compiler and Visual Studio to detect potential nullability issues during development, improving overall code quality. Related Thread

Benefits

• Detects null reference issues at compile time rather than runtime
• Provides clearer annotations for nullable and non-nullable values
• Enhances code safety and maintainability
• Improves IDE support for nullability analysis

Success Criteria

• Nullable reference types are enabled in all projects
• No compiler warnings related to nullability remain
• All tests pass successfully