docs: Add pull request template cookbook with examples and guidelines

[gauransh]

Pull Request Template: Adding Pull Request Template Guide

What?

This PR introduces a comprehensive guide for writing Pull Request Templates (PRT), including examples, best practices, and templates to help developers create clear, structured, and efficient pull requests.

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Why?

To provide a standardized approach to submitting pull requests, ensuring consistency, improving communication, and making the review process smoother for the entire team.

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How?

• Edited the existing pull_requests.md file in the resources/readings/cookbooks/ directory.
• Updated the document with detailed pull request templates, best practices, and real-world examples for different scenarios (e.g., feature implementation, bug fixes).
• Structured the guide to serve as a reference for developers when submitting PRs.

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Type of Change

• ✨ Feature (adds new functionality)
• 🧹 Chore (documentation, cleanup, etc.)