Refactor: centralize config/state in Configuration.cs
Moved all benchmark configuration, mutable state, and attribute-flag aggregation from Program.cs to a new Configuration.cs static class. Updated all references in Program.cs and related benchmark classes to use Configuration.<value>. Removed the "profiler" CLI mode and its code. Updated README.md to reflect these changes. This improves maintainability and keeps Program.cs focused on orchestration and UX, with no changes to benchmark logic.
