Install git in Docker image for Hugging Face Spaces build system

Dockerfile

@@ -19,7 +19,9 @@
 
 FROM python:3.12-slim
 
-# Install uv (fast Python package manager)
+# Install git (required by Hugging Face Spaces build system) and uv
+RUN apt-get update && apt-get install -y --no-install-recommends git \
+    && rm -rf /var/lib/apt/lists/*
 RUN pip install --no-cache-dir uv
 
 WORKDIR /app