MSVC transitively includes <memory> via other headers, masking the
missing include. GCC 11.4 requires it explicitly for std::shared_ptr.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Initial commit: C++ actor-based matching engine (Optiq architecture)
Port of StockEx Python prototype to C++ with Simplx-compatible actor framework.
Includes price-time priority OrderBook, OEGateway/OrderBook/MarketData actors,
Recovery Cause/Effect (Master/Mirror HA), IACA fragment chain aggregation,
and 20 passing tests.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
