feat: Implement initial version of the channel app

[p018841p-coder]

This commit introduces the initial version of the real-time channel chat application.

Key Features:

• A server built with Node.js, Express, and Socket.IO.
• A client-side interface built with HTML, CSS, and vanilla JavaScript.
• Password protection: Users must enter a correct password to join the chat.
• Background color customization: Users can change the background color of the chat window.

Project Structure:

• server/: Contains the backend Node.js application.
• client/: Contains the frontend HTML, CSS, and JavaScript files.

Description

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Fixes # (issue)

Checklist

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• [ ] My code follows the code style of the project.
• [ ] I have updated the documentation (if applicable).
• [ ] I have added tests to cover my changes.

Type of Change

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• [ ] Bug fix (non-breaking change which fixes an issue)
• [ ] Documentation update (non-breaking change which updates documentation)
• [ ] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to not work as expected)

Screenshots

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Additional Notes

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