🔒 Fix XSS vulnerability by strictly configuring DOMPurify

[julesklord]

🎯 What: An XSS vulnerability existed where DOMPurify was used without explicit configuration inside a dangerouslySetInnerHTML block.
⚠️ Risk: Relying on default configuration of sanitization libraries can leave edge case vulnerabilities or fail strict code scanning checks, allowing potential malicious script execution.
🛡️ Solution: Configured DOMPurify with an explicit ALLOWED_TAGS and ALLOWED_ATTR list to strictly enforce expected structure and safely render syntax-highlighted code.

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PR created automatically by Jules for task 18079693561575940036 started by @julesklord

[google-labs-jules]

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