Ship portable CPU dispatch and verified shared runtime dependencies

docs/SEMANTIC.md

@@ -28,8 +28,13 @@ retry of that request. WorkerInfo and responses report the actual device.
 **Windows VM tests remain CPU only**, via SEARCHI_FORCE_CPU=1 and Device::Cpu.
 GPU execution/failure recovery has not been exercised here.
 
-The Windows worker links a static MSVC CRT and static llama libraries, without
-an external OpenMP runtime. Production CMake supports cpu, auto, metal, vulkan,
+The normal Windows x64 worker ships shared llama libraries and baseline plus
+optimized CPU modules. Selection checks CPU features and OS support for AVX
+register state; it loads packaged backends from the executable directory.
+Shared libraries use a common MSVC CRT because model file handles cross DLL
+boundaries. The unchanged release CRT files are packaged alongside the worker.
+Internal static CPU builds retain a static CRT. Neither profile requires an
+external OpenMP runtime. Production CMake supports cpu, auto, metal, vulkan,
 and cuda; CPU builds force GPU flags off. Runtime/provider parity and packaging
 on other operating systems remain independent release checks.