Reviews and refactors .NET/C# code: fixes async patterns, validates DI registration, corrects error handling, adds documentation, enforces style conventions. USE FOR: review C# code, audit project, enforce coding standards, apply .NET best practices, clean up code, fix style issues, apply coding standards, tidy up this file, make this idiomatic C#, fix code quality issues, get PR-ready, prepare for code review, add documentation, fix async patterns, check DI registration, check error handling, fix configuration, bring this up to standard, make this code production-ready. DO NOT USE FOR: non-.NET codebases, read-only .NET questions, trivial single-variable edits.