Refactor AcBinaryHubProtocol for thread safety
- Removed shared _currentHeaderContext; header context is now passed as a parameter through Parse* and ReadArguments/ReadSingleArgument methods, and stored per-binder for chunked messages.
- Updated AyCodeBinaryHubProtocol to use the new header context flow for type resolution and argument deserialization.
- Added concurrency tests to verify protocol instance safety under multi-threaded use and prevent state corruption or type resolution races.
- Improved documentation and comments to clarify the stateless, concurrency-safe design.
