Add http request headers

[boomzero]

What does this PR aim to accomplish?:

This pull request includes updates to the XMOJ.user.js script to enhance API requests and improve the rendering process for MathJax. The most important changes include adding new headers to the API requests and ensuring that MathJax rendering is awaited properly.

How does this PR accomplish the above?:

Enhancements to API requests:

• XMOJ.user.js: Added new headers XMOJ-UserID, XMOJ-Script-Version, and DebugMode to the RequestAPI function to provide more context and control over the requests.

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[github-actions]

Qodana for JS

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