Repo-wide sweep with the pinned CSharpier 1.3.0 tool. Whitespace and line-wrapping only; OpenNest.Engine.Tests (109) and OpenNest.IO.Tests pass after reformat, full solution builds 0 errors. Added .csharpierignore so csproj/config XML keeps its existing layout (CSharpier's XML wrapping churns attributes with zero benefit). Formatting is now enforceable: dotnet csharpier check . passes.