Initial commit: Future-Entropy Sampler prototype

llama.cpp-based implementation of the countbayesie Future-Entropy Sampler,
built via a direct ctypes binding to libllama.so. Includes a one-shot CLI
(entropy_cli.py), an OpenAI-compatible server (entropy_server.py), and the
tuning/benchmark scripts used to derive the alpha/confidence-threshold
defaults documented in the README.

Model path and llama.cpp library path are now read from environment
variables (ENTROPY_SAMPLER_MODEL, LLAMA_CPP_LIB) instead of being hardcoded,
and gguf-py is pulled from PyPI instead of a local llama.cpp checkout, so
this runs on any machine with a compatible llama.cpp build and model.

requirements.txt

@@ -0,0 +1,5 @@
+numpy>=2.0
+gguf>=0.16
+jinja2>=3.1
+fastapi>=0.110
+uvicorn>=0.30