feat: add thorough Queue explanation and multiple implementations (Python)

[UserAkku]

#What this PR adds

Adds Python/data_structures/queue_explained.py — an educational file that
explains the Queue data structure with multiple implementations (Simple list-backed,
Circular array, Linked-List), complexity analysis, and tests/examples.

Why this is useful

• Helps beginners understand FIFO and different implementation trade-offs.
• Contains runnable tests and demo sections for quick verification.

Thanks for maintaining this amazing repo! 🙌

[github-actions]

🎉 Welcome to Hacktoberfest 2025, @UserAkku! 🎃

Thank you for your first contribution to our DSA repository! Here's what happens next:

🔍 Automatic Checks

• ✅ Code Validation: Passed
• 🧪 Compilation Tests: Passed

📋 Next Steps

🎯 Great job! Your code compiled successfully. Maintainers @Karanjot786 and @Pradeepsingh61 will review your PR soon.

🎁 What You Get

• 🏆 Hacktoberfest Credit: This PR counts toward your 6 PR goal for exclusive T-shirt + Tree!
• 🌟 Hall of Fame: You'll be featured in our contributors list
• 📚 Learning: Code review feedback from experienced developers

💡 Tips for Success

• Follow our Contributing Guidelines
• Add comments explaining your algorithm
• Include time/space complexity analysis
• Test your code before submitting

Welcome to the community! 🚀

[github-actions]

🤖 Automated PR Status

🔍 Code Validation

✅ Passed - File naming and structure look good!

🧪 Compilation Tests

✅ Passed - All code compiles successfully!

📋 Overall Status

🎉 Ready for Review - Your PR has passed all automated checks!
👥 Maintainers have been notified for review.

---

This comment was generated automatically. Checks will re-run when you push new commits.