Refactor Fast Modular Exponentiation: clean code and minimal includes

[ak4shravikumar]

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Pull Request Template

Description

This pull request consolidates 40 separate import statements into a single, organized import to improve code readability, reduce redundancy, and simplify maintenance. This change does not affect the existing functionality of the project but makes the code cleaner and easier to manage.

Fixes #6

Type of Change

• New feature (non-breaking change which adds functionality/optimizes code)

How Has This Been Tested?

The code was tested by running the full application and verifying that all modules imported correctly and no functionality broke due to the change.

• Verified application runs without import errors
• Checked existing functionalities that depend on the imports

Test Configuration:

• Firmware version: N/A
• Hardware: Local development machine
• Toolchain: Python 3.x
• SDK: N/A

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules

Additional Information

This enhancement reduces the number of imports from 40 to 1 without breaking functionality and improves maintainability for future contributions.

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