C# implementation of the language #501
Description
Motivation
A user working within the .NET ecosystem would benefit significantly from this feature, especially considering OpenFGA already provides a .NET SDK.
Having first-class language support for C# would complete the developer experience by allowing users to parse, transform and validate models without having to use the Open CLI for that - staying within their ecosystem.
Implementation Details and Acceptance Criteria
The suggested implementation approach is to define the C# grammar using ANTLR , consistent with other language implementations in this repository.
In order to be accepted, the new C# implementation must passes all existing shared tests defined within the repository to guarantee full compatibility with the OpenFGA syntax and specification.
It must also use the same conventions, workflows and documentation as the rest of the language implementations