
Parallel State

✅ Concurrent branch execution using asyncio.gather()
✅ Multiple state types in branches (Pass, Wait, Fail, etc.)
✅ Path processing (InputPath, ResultPath, OutputPath, ResultSelector)
✅ Error handling - any branch error fails the entire parallel state
✅ Comprehensive validation - all AWS States Language rules enforced
✅ 20+ test cases covering all scenarios from the Go implementation
