Agent Skills: qa-testing-nunit

Design and refactor C# test suites with NUnit for API, component, and integration scenarios. Use when creating or fixing NUnit fixtures, structuring test projects, setting up WireMock and Testcontainers dependencies, and reducing flaky behavior in CI or local runs. For general backend service implementation use $software-csharp-backend, for pipeline target changes use $ops-nuke-cicd, and for logging-migration rewrites use $dev-structured-logs.