Refactor third-party integrations to use a shared HTTP client

[vraj826]

Description

Introduced a shared HTTP client and refactored all third-party integrations to use a common request layer. This centralizes timeout handling, response validation, JSON parsing, and error normalization while preserving existing fallback behavior.

Related Issue

Closes #163

Type of Change

• Refactor
• Performance improvement

Changes Made

• Added a shared HTTP client (src/utils/http-client.js) for external API communication
• Refactored GitHub REST, GitHub GraphQL, LeetCode, Codeforces, and CodeChef services to use the shared client
• Centralized timeout handling, JSON parsing, status validation, user-agent headers, and structured error normalization
• Added unit tests for the HTTP client and integration-level service behavior
• Preserved existing graceful degradation and fallback logic for optional integrations

Testing

• Ran npm test — all tests pass
• Tested manually (if applicable)

Verification performed:

• npm.cmd run lint → passing
• npm.cmd run test:unit → passing (12 suites, 141 tests)

Screenshots (if applicable)

N/A

Checklist

• My code follows the project's code style
• I have performed a self-review of my code
• I have commented my code, particularly in hard-to-understand areas
• My changes generate no new warnings or errors
• I have updated the documentation if necessary
• My changes are scoped to a single issue

[vercel]

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[vraj826]

@SamXop123 Can you review the changes!

[vercel]

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Project	Deployment	Actions	Updated (UTC)
samdev-pulse	Ready	Preview, Comment	Jun 9, 2026 5:58pm

[SamXop123]

Looks solid! thank you for the contribution

[github-actions]

🎉 Congratulations @vraj826! 🎉

Your pull request has been successfully merged into samdev-pulse! Thank you so much for your valuable contribution and effort. Every single improvement helps make samdev-pulse a better profile experience for everyone! 🙌

🚀 What's Next?

• Keep the momentum going! Feel free to browse through our open Issues and grab another one that interests you!
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Have any questions, want feedback, or just want to discuss further contributions? Feel free to reach out directly to the maintainer on Discord: dot_notsam!

Thank you again, and keep up the amazing work! 💻✨