Fix: Replaced shell form with exec form and corrected typo in README.md

What was changed

1. Replaced shell form with exec form in Dockerfile:
   • Updated CMD to use exec form for better consistency and reliability.
2. Corrected typo in README.md:
   • Replaced thredhold with threshold for improved clarity and professionalism.

Why these changes were made

• Using exec form in CMD instructions is recommended as it avoids issues with signal forwarding and improves container behavior.
• Fixing typos ensures documentation is clear, professional, and easy to understand for readers.

Additional Notes

• These changes improve Dockerfile consistency and the quality of documentation without altering functionality.