Enhance Documentation: Added "Usage Example" Section and Dedicated USAGE_EXAMPLE.md Guide

[Aspirant200715]

This PR enhances the repository’s documentation by adding a detailed “Usage Example” section and a new file named USAGE_EXAMPLE.md.
The goal is to help beginners and first-time contributors understand how to clone, run, test, and contribute to this repository more effectively.

🧠 What’s New
📝 1. New Section in README

Added a new “Usage Examples” section below the main content.

This section provides:

Step-by-step guide to clone and explore the repo.

1. Instructions on how to run and test algorithms.
2. Example command outputs for key algorithms (Bubble Sort, Dijkstra, etc.).
3. Clear explanation of folder structure and file organization.
4. Contribution best practices for new algorithms.
5. Example code template with docstrings and complexity analysis.

📄New File: USAGE_EXAMPLE.md

A standalone, detailed version of the usage guide for easier access.

Includes:
Installation and setup instructions
Folder walkthrough
Running algorithms with examples
Unit testing commands
Steps to add a new algorithm (template included)
PR and contribution workflow summary
List of potential algorithm ideas for contribution

This file acts as a “Getting Started + How to Contribute” manual for new developers.

Fixes issue #13714