Update calculateCompoundInterest.py

[Om149]

Refactored the code into clear, modular functions: get_user_input(), calculate_future_value(), and main().

Replaced repetitive prints with emoji-enhanced UI prompts for better readability.

Added basic input validation and error handling.

Applied consistent formatting and added inline comments to clarify logic.

Removed unnecessary conditions from loop.

PR Title

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Summary

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Description

The changes are as follows:

• Change 1
• Change 2

Checks

in the repository

• [ ] Made no changes that degrades the functioning of the repository
• [ ] Gave each commit a better title (unlike updated README.md)

in the PR

• [ ] Followed the format of the pull_request_template
• [ ] Made the Pull Request in a small level (for the creator's wellfare)
• [ ] Tested the changes you made

Thank You,

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