Add HTML sanitization and error handling to MarkdownPreview

[Copilot]

Addresses two security and robustness issues in the MarkdownPreview component:

Changes

• HTML Sanitization: Added rehype-sanitize to the ReactMarkdown rehypePlugins chain after rehypeRaw to prevent XSS from AI-generated content
• Clipboard Error Handling: Wrapped navigator.clipboard.writeText() in try/catch to handle permission errors and prevent unhandled rejections

// Before
rehypePlugins={[rehypeRaw]}

// After  
rehypePlugins={[rehypeRaw, rehypeSanitize]}

// Before
const handleCopy = async () => {
  await navigator.clipboard.writeText(content);
  setCopied(true);
  setTimeout(() => setCopied(false), 2000);
};

// After
const handleCopy = async () => {
  try {
    await navigator.clipboard.writeText(content);
    setCopied(true);
    setTimeout(() => setCopied(false), 2000);
  } catch (error) {
    console.error('Failed to copy to clipboard:', error);
    setCopied(false);
  }
};

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Project	Deployment	Actions	Updated (UTC)
readme-gen-ai	Ready	Preview, Comment	Feb 12, 2026 4:31pm

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