docs: update E2E tests refactoring plan to reflect current state

- Correct line count from 437 to 427 lines (42% reduction from original 735)
- Update file paths to reflect actual command_wrappers/ structure
- Add missing implemented features (4-stage framework, embedded templates, error recovery)
- Recognize current implementation as well-structured rather than needing complete rewrite
- Update priorities to focus on configuration management and observability enhancements
- Revise roadmap phases to build on existing solid foundation
- Fix technical debt analysis to reflect actual current code state
- Update architecture proposal to show realistic next steps
- Correct dates to September 10, 2025

Author: josecelano