Fix: Make build script cross-platform (replace cp with cpy) for Windows

[deepanshurajput0]

Summary

This PR fixes the build script so it works on Windows environments.

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Problem

The current build script uses the Unix-only cp command, which causes the build to fail on Windows. As a result, files including icons/, manifest.json, and popup.html are not copied into the dist/ folder, and Chrome fails to load the extension.

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Solution

Replaced the Unix-specific cp commands with the cross-platform cpy package:

"build": "npm run sync-version && tsc && cpy src/manifest.json dist/ && cpy src/popup.html dist/ && cpy src/icons/**/* dist/icons/"

This ensures the build works on Windows while preserving existing behavior on macOS/Linux.

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Tested Environment

• OS: Windows 11
• Node.js: v22.12.0
• npm: 10.9.0

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References

Fixes #15