fix: 修复代码长度单位换算错误

[boomzero]

What does this PR aim to accomplish?:

This pull request includes changes to the XMOJ.user.js file, focusing on improving memory size representation and updating label lists. The most important changes include the addition of a new function for memory size conversion and modifications to how memory sizes are displayed.

Closes #706

How does this PR accomplish the above?:

• XMOJ.user.js: Added a new function CodeSizeToStringSize to convert memory sizes into human-readable formats with units (B, KB, MB, GB). This function includes error handling and debug mode alerts.
• XMOJ.user.js: Updated the main function to use the new CodeSizeToStringSize function for converting memory sizes, replacing the previous SizeToStringSize function.

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[github-actions]

Qodana for JS

3 new problems were found

Inspection name	Severity	Problems
Expression statement which is not assignment or call	◽️ Notice	3

💡 Qodana analysis was run in the pull request mode: only the changed files were checked
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