shm Directory Reference

Files
	futex.hpp
	Cross-platform futex-like synchronization primitives.
	mpsc_shm.cpp
	mpsc_shm.hpp
	Multi-Producer Single-Consumer via SPSC rings + doorbell futex.
	spsc_shm.cpp
	spsc_shm.hpp
	Single-producer/single-consumer shared-memory ring buffer (Linux, x86-64 optimized)
	utilities.hpp
	Common utilities for IPC shared memory implementation.