feat: make GitHub repository URL configurable

[ShashwatUpadhayay]

Summary

• Read the GitHub repository URL from NEXT_PUBLIC_GITHUB_REPO_URL
• Fall back to https://github.com/O2sa/DevImpact when the variable is not set
• Document the new environment variable in .env.example

Testing

• Verified the link opens the default repository when the environment variable is unset.
• Verified the link opens the configured repository URL when NEXT_PUBLIC_GITHUB_REPO_URL is set.

close #162

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[github-actions]

Thank you for the pull request! ✅

A maintainer will review this soon. Please be patient while we take a look. 🙌

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Project	Deployment	Actions	Updated (UTC)
dev-impact	Ready	Preview, Comment	Jun 20, 2026 7:53pm

[github-actions]

🎊 Welcome, @ShashwatUpadhayay! Your first contribution has been merged! 🚀

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