feat: Implement repository restructuring plan with detailed phases and tasks

- Added comprehensive implementation plan for repository restructuring in plan.md
- Created feature specification document outlining goals, user stories, and proposed solutions in spec.md
- Established task tracking document for each phase of the restructuring process in tasks.md
- Defined directory structure and metadata schema for improved organization and discoverability
- Set up initial utilities for content migration and validation

Author: PowerAppsDarren