Fix Dockerfile: copy src before pip install; set PYTHONPATH

Dockerfile

@@ -39,15 +39,15 @@ RUN apt-get update && apt-get install -y --no-install-recommends \
     poppler-utils \
     && rm -rf /var/lib/apt/lists/*
 
-# Install Python dependencies
+# Copy project metadata and source before installing
 COPY pyproject.toml ./
-RUN pip install --upgrade pip && pip install .
-
-# Copy source
 COPY src/py_docx ./src/py_docx
 
-# Ensure py_docx is importable
-ENV PYTHONPATH="/app/src:${PYTHONPATH}"
+# Install Python dependencies (including this package)
+RUN pip install --upgrade pip && pip install .
+
+# Ensure py_docx is importable at runtime
+ENV PYTHONPATH="/app/src"
 
 # Create runtime dirs
 RUN mkdir -p /templates /out /tmp/py-docx-mcp