Add missing community health files and templates

[tech0priyanshu]

Summary

We are missing several recommended community health files that help contributors collaborate effectively and securely.

Tasks

• Add a Code of Conduct (CODE_OF_CONDUCT.md)
• Add Contributing Guidelines (CONTRIBUTING.md)
• Add a Security Policy (SECURITY.md)
• Create Issue Templates
  • Bug Report Template
  • Feature Request Template
• Create Pull Request Template (PULL_REQUEST_TEMPLATE.md)

Benefits

• Provides clear contribution guidelines
• Improves security vulnerability reporting
• Standardizes issue and PR submissions
• Enhances repository professionalism and maintainability

References

GitHub Community Standards:
https://docs.github.com/en/communities