Change Dockerfile to use main.py instead of main_sdxl.py for CCO model integration

Dockerfile

@@ -63,5 +63,5 @@ HEALTHCHECK --interval=30s --timeout=10s --start-period=60s --retries=3 \
 ENTRYPOINT ["/entrypoint.sh"]
 
 # Run the application (port will be set via environment variable)
-# Use SDXL version for text-guided colorization
-CMD ["sh", "-c", "uvicorn app.main_sdxl:app --host 0.0.0.0 --port ${PORT:-7860}"]
+# Use main.py with GAN and CCO colorization models
+CMD ["sh", "-c", "uvicorn app.main:app --host 0.0.0.0 --port ${PORT:-7860}"]