fix: copy README.md into Docker image for hatchling metadata

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Dockerfile

@@ -7,10 +7,10 @@ RUN apt-get update && apt-get install -y --no-install-recommends \
     && rm -rf /var/lib/apt/lists/* \
     && npm install -g @getgrit/cli
 
-COPY pyproject.toml .
+COPY pyproject.toml README.md ./
 COPY src/ src/
 
-RUN pip install --no-cache-dir -e .
+RUN pip install --no-cache-dir .
 
 ENV GRADIO_SERVER_NAME="0.0.0.0"
 ENV GRADIO_SERVER_PORT="7860"