Refactor YOLOv5 code for readability, maintainability, and efficiency

[sanowl]

This pull request refactors the YOLOv5 codebase to enhance readability, maintainability, and efficiency. Key improvements include:

• Added comprehensive comments and docstrings for better clarity.
• Introduced type hints to improve code understanding and maintainability.
• Enhanced modularity by structuring functions and classes.
• Reformatted the code according to PEP 8 guidelines for improved readability.
• Improved error handling during model testing.

These changes aim to make the code more maintainable, readable, and easier to understand for current and future developers.

🛠️ PR Summary

_{Made with ❤️ by Ultralytics Actions}

🌟 Summary

Minor typo correction in the YOLOv5 classification model code.

📊 Key Changes

• Fixed a typo in the constructor docstring: corrected "cuttoff" to "cutoff".

🎯 Purpose & Impact

• Improved Readability: Enhances documentation accuracy and readability 💻✨.
• User Confidence: Small corrections can build overall confidence in the quality and maintainability of the codebase.

[github-actions]

Thank you for your submission, we really appreciate it. Like many open-source projects, we ask that you all sign our Contributor License Agreement before we can accept your contribution. You can sign the CLA by just posting a Pull Request Comment same as the below format.

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I have read the CLA Document and I sign the CLA

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1 out of 2 committers have signed the CLA.
✅ (UltralyticsAssistant)[https://github.com/UltralyticsAssistant]
❌ @sanowl
_{You can retrigger this bot by commenting recheck in this Pull Request. Posted by the CLA Assistant Lite bot.}

[github-actions]

👋 Hello @sanowl, thank you for submitting a YOLOv5 🚀 PR! To allow your work to be integrated as seamlessly as possible, we advise you to:

• ✅ Verify your PR is up-to-date with ultralytics/yolov5 master branch. If your PR is behind you can update your code by clicking the 'Update branch' button or by running git pull and git merge master locally.
• ✅ Verify all YOLOv5 Continuous Integration (CI) checks are passing.
• ✅ Reduce changes to the absolute minimum required for your bug fix or feature addition. "It is not daily increase but daily decrease, hack away the unessential. The closer to the source, the less wastage there is." — Bruce Lee

[glenn-jocher]

@sanowl hello,

Thank you for your pull request and for contributing to the YOLOv5 project! We appreciate your efforts to enhance the readability, maintainability, and efficiency of the codebase. Your detailed changes, including the addition of comprehensive comments, type hints, and adherence to PEP 8 guidelines, are highly valuable.

To ensure a smooth integration, could you please confirm that your changes are compatible with the latest versions of torch and the YOLOv5 repository? This helps us maintain consistency and avoid potential conflicts.

Additionally, if you have any specific examples or tests that demonstrate the improvements and verify the functionality of your refactored code, please include them. This will help us thoroughly review and validate your contributions.

For further guidance on creating reproducible examples, you can refer to our minimum reproducible example documentation.

Thank you again for your valuable contributions. We look forward to reviewing your changes!