Implement FizzBuzz in Cairo

[GideonBature]

Overview

This PR implements the classic FizzBuzz problem in Cairo as requested in issue #216. The implementation follows the standard rules:

• For numbers divisible by 3, print "Fizz"
• For numbers divisible by 5, print "Buzz"
• For numbers divisible by both 3 and 5, print "FizzBuzz"
• Otherwise, print the number itself

Implementation Details

• Created a new Scarb project in examples/cairo/scripts/fizzbuzz/
• Implemented the main fizzbuzz function that takes a number n and returns an array of strings from 1 to n
• Created a utility function u32_to_felt252 to convert numbers to string representation
• Added comprehensive test cases covering multiple edge cases

File Structure

• .tool-versions: Specifies Scarb version 2.11.2
• Scarb.toml: Project configuration
• src/fizz_buzz.cairo: Main FizzBuzz implementation
• src/utils/number_converter.cairo: Utility functions for number-to-string conversion
• tests/test_fizzbuzz.cairo: Test cases validating the implementation

Testing

The implementation includes tests for various input values:

• Test with n=3: Validates handling of numbers 1-3, including the "Fizz" case
• Test with n=5: Validates handling of numbers 1-5, including both "Fizz" and "Buzz" cases
• Test with n=15: Comprehensive test covering all possible cases including "FizzBuzz"

All tests pass successfully, confirming the implementation meets the requirements specified in issue #216.

🖼️ Screenshots (if applicable)

Related Issue

Closes #216