.NET Compaction - Implement Alternative Compaction Architecture

[crickman]

Design and implement an alternative solution that introduces direct compaction support into the core agent architecture.

Adapt existing compaction strategies, pipeline concepts, and samples to work with the alternative architecture.

Review the alternative architecture with Wesley and collect feedback on design tradeoffs, feasibility, and alignment with requirements.

Update and refine based on feedback and further analysis to improve clarity, robustness, and developer experience.