add installation scripts and project documentation

[itashia]

Pull Request

Summary

Add Hive installer scripts and improve project documentation for easier installation and onboarding.

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Type of Change

• Bug fix
• New feature
• Improvement
• Performance optimization
• Refactoring
• Documentation update
• CI / Build
• Dependencies
• Other

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Related Issue

Closes #

or

Related to #

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What Changed?

• Added automated installation scripts for Linux and Windows.
• Added Linux installer using curl with automatic latest release detection.
• Added Windows PowerShell installer with PATH configuration.
• Added complete README documentation including installation, usage, commands, and development setup.

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Testing

How was this tested?

• Tested on Windows
• Tested on Linux
• Tested on macOS
• Unit tested
• Manually tested

Test Steps

1. Tested installer scripts locally.
2. Verified Hive binary download from GitHub Releases.
3. Verified installed command is accessible through terminal.

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Screenshots

N/A

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Checklist

• My code follows the project's style.
• I have tested my changes.
• I updated the documentation if needed.
• I added or updated tests where applicable.
• This PR does not introduce unnecessary breaking changes.
• I have reviewed my own code before requesting review.

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Additional Notes

This PR improves the Hive CLI onboarding experience and makes installation easier for new users across different platforms.