Add Jump Search algorithm in searching/jump_search.cpp

[saksham23467]

Description of Change

Added a C++ implementation of the Jump Search algorithm in searching/jump_search.cpp.
The implementation includes:

• A function jump_search with proper documentation
• An example usage in the main() function
• Inline comments for clarity following Doxygen style

Checklist

• Added description of change
• Added file name matches File name guidelines
• Added tests and example, test must pass
• Added documentation so that the program is self-explanatory and educational - Doxygen guidelines
• Relevant documentation/comments is changed or added
• PR title follows semantic commit guidelines
• Search previous suggestions before making a new one, as yours may be a duplicate.
• I acknowledge that all my contributions will be made under the project's license.

Notes

This is my first open source PR. Feedback is welcome!