I have a collection of Java / Kotlin classes that sit at the heart of my Android app. They manage in-memory data structures, expose that data to the rest of the app, and synchronise it with our back-end through a handful of REST-style APIs. I now need the exact same behaviour expressed in clean, idiomatic C# so the project can be compiled under the .NET Android toolchain (Xamarin or MAUI—whichever you prefer). Your task is to translate every class, interface, and public method signature to their .NET equivalents, preserving naming, access levels, and logic while embracing C# conventions such as properties, async/await, and nullability annotations. The resulting code must build and run in Visual Studio, target current Android SDK levels, and integrate with the existing API endpoints exactly as the original does. I will supply: • The full Java/Kotlin sources, unit tests, and example API payloads. • A short README explaining the data flow and expected edge-case behaviour. I expect back: • A C# project folder with the converted classes ready to drop into my solution. • Lightweight unit tests showing parity with the original behaviour (NUnit or xUnit are both fine). • A brief migration note highlighting any language-driven deviations or improvements you introduced. No UI work is required—this is purely about data handling and API interaction. If you have already migrated logic like this before and know your way around HttpClient, System.Text.Json, and Task-based patterns, you’ll feel right at home.