Fix Dockerfile (use $MODEL_URL) and README front-matter

Dockerfile

@@ -2,7 +2,7 @@ FROM ghcr.io/ggerganov/llama.cpp:server
 
 ENV MODEL_URL="https://huggingface.co/bartowski/Qwen2.5-0.5B-Instruct-GGUF/resolve/main/Qwen2.5-0.5B-Instruct-Q4_K_M.gguf"
 
-RUN mkdir -p /models && curl -L -o /models/model.gguf %MODEL_URL%
+RUN mkdir -p /models && curl -L -o /models/model.gguf $MODEL_URL
 
 EXPOSE 7860
-CMD ["llama-server", "-m", "/models/model.gguf", "-c", "2048", "-ngl", "0", "-t", "4", "--host", "0.0.0.0", "--port", "7860"]
+CMD ["llama-server","-m","/models/model.gguf","-c","2048","-ngl","0","-t","4","--host","0.0.0.0","--port","7860"]