Dependency Injection Patterns When to Use This Skill Use this skill when: - Organizing service registrations in ASP.NET Core applications - Avoiding massive Program.cs/Startup.cs files with hundreds of registrations - Making service configuration reusable between production and tests - Designing libraries that integrate with Microsoft.Extensions.DependencyInjection --- The Problem Without organization, Program.cs becomes unmanageable: Problems: - Hard to find related registrations - No clear boundaries between subsystems - Can't reuse configuration in tests - Merge conflicts in team settings…