feat: add bigInt function to Number module

[Daniel-Grounin]

Summary

Added a bigInt function to the Number module that generates random BigInt values between a specified range, with optional parameters for min and max. This function follows the format of existing methods and supports edge cases like negative values and exact range matches.

Changes

• Implemented bigInt in number.cpp and added declarations in number.h.
• Wrote unit tests in number_test.cpp to verify functionality for valid, negative, and exact ranges.
• Verified that all tests pass successfully.

Tests

All relevant tests for the bigInt function pass.

Let me know if further changes are required! 😊

[cieslarmichal]

For some reason in your changes all lines are deleted and then inserted, maybe line ending or something? Please take a look at that because I cant review it properly, not sure what changed