Added snippet: Calculate date difference in days

[harishkSN]

PR Description:

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Pull Request Checklist

Overview

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• I have read and understood the CONTRIBUTING.md guidelines
• My pull request has a descriptive title that accurately reflects the changes and the description has been filled in above.
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• I've created a new branch in my forked repository for this contribution

Code Quality

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[github-actions]

Thank you for your contribution. However, it doesn't comply with our contributing guidelines.

As a reminder, the general requirements (as outlined in the CONTRIBUTING.md file) are the following: follow the folder+subfolder guidelines and include a README.md file explaining what the code snippet does.

Validation errors:

Folder structure violations found:
 - Move 'Server-Side Components/harishk_DateDifferenceSnippet.js' under a valid folder hierarchy (Category/Subcategory/Use-Case/your-file). Files directly inside 'Server-Side Components' or its subcategories are not allowed.

Review your contribution against the guidelines and make the necessary adjustments. Closing this for now. Once you make additional changes, feel free to re-open this Pull Request or create a new one.