docs: Add T042 REST audit completion report

Complete documentation of T042 deliverables:
- Automated audit script execution results
- 77 violations identified across 72 routes
- HIGH severity fixes (5 PUT endpoints) - COMPLETE
- MEDIUM severity fixes (5 response format) - COMPLETE
- LOW severity fixes (67 OPTIONS) - Optional Phase 4
- 35 unit tests passing (100% coverage)
- 18,000+ lines documentation
- Production deployment guide ready

Status:  COMPLETE - Ready for production deployment

Author: rafiqul4