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

Please include a summary of the change and which issue is fixed. Please also include relevant motivation and context.

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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