Use python3 in CMD and simplify mkdir

Dockerfile

@@ -35,9 +35,7 @@ RUN pip install --no-cache-dir -r requirements.txt
 COPY . .
 
 # Create necessary directories
-RUN mkdir -p output && \
-    mkdir -p pdfs && \
-    mkdir -p uploads
+RUN mkdir -p output pdfs uploads
 
 # Expose Hugging Face Spaces default port
 EXPOSE 7860
@@ -47,4 +45,5 @@ HEALTHCHECK --interval=30s --timeout=10s --start-period=40s --retries=3 \
     CMD curl -f http://localhost:7860/ || exit 1
 
 # Run Flask app
-CMD ["python", "app.py"]
+# Use python3 explicitly and ensure we're in the right directory
+CMD ["python3", "app.py"]