Add comprehensive Google Drive integration documentation

Detailed guide covering all aspects of the new Drive integration:
- Complete implementation overview
- Component descriptions (setup script, framework, sweeps)
- Validation results (335 combinations, 100% success)
- File format specifications (JSON, CSV, metadata, reports)
- Usage workflows and examples
- Troubleshooting guide
- Migration guide from old system

Provides complete reference for using the new automatic
Google Drive synchronization system for all simulation results.

Author: claude