- Implement backtest workflow validation for headless operator mode
- Add handoff evidence tracking for backtest runs
- Update operator client, runner, scenario, and output modules
- Add test files for handoff, backtest runner, and error handling
- Add test data for backtest scenarios and validation
- Add proto files for backtest and market domains
- Generate Go code in packages/contracts/gen/go
- Generate Dart code in apps/client/lib/src/generated
- Add contracts-gen and contracts-check binaries
- Update pubspec.yaml with protoc dependencies
- Update go.work with new module