Change Dockerfile ordering

backend/Dockerfile

@@ -10,10 +10,15 @@ RUN apt-get update && apt-get install -y --no-install-recommends \
 
 # Install Python dependencies
 COPY pyproject.toml README.md alembic.ini ./
-COPY src/ ./src/
+
+# Create minimal package stub so editable install can resolve the package
+RUN mkdir -p src/app && touch src/app/__init__.py
 
 RUN pip install --no-cache-dir -e .
 
+# Copy source (will be overridden by volume mount in dev)
+COPY src/ ./src/
+
 # Expose port
 EXPOSE 8000