frontend: adds preview to html code snippets

[tomtobac]

Description

Adds preview to Pre component to render HTML blocks using iframes

• Issue: OS-1985
• Dependencies: No dependencies

AI Description

This pull request introduces a new feature that allows users to include code blocks in their messages, which will be displayed as interactive iframes.

Changes include:

• New utility functions addOnErrorToImg and getReconstructedHtml in preview.ts to process and reconstruct HTML from a plain string.
• New Iframe component in Iframe.tsx that renders an iframe with a lazy loading mechanism. It also includes a SyntaxHighlighter to style the code.
• Updates to package.json and package-lock.json to include new dependencies required for the new feature.
• Modifications to MessageContent.tsx to incorporate the isFulfilledMessage type and utilize the replaceCodeBlockWithIframe function to replace code blocks with iframes.
• Changes to Markdown.tsx to import the Iframe component and update the rehypePlugins to include rehypeRaw.