Add Genmoji support

[dcalhoun]

What problem does this address?

Genmoji are available in every app, but they require a bit of work to render them as emoji. By default, these are inserted as images, which is not what you typically want.

Screenshots

Generation	Current Result

References:

• https://developer.apple.com/videos/play/wwdc2024/10220/
• https://developer.apple.com/documentation/uikit/nsadaptiveimageglyph

What is your proposed solution?

We should implement logic to render Genmoji as emoji characters.

// Converting NSAttributedString to HTML
let htmlData = try textContent.data(from: NSRange(location: 0, length: textContent.length),
documentAttributes: [.documentType: NSAttributedString.DocumentType.html])

<!-- Resulting HTML-->
<picture>
  <source srcset="genmoji.heic" type="image/x-apple-adaptive-glyph">
  <img src="genmoji.png" alt="dog in a spacesuit">
</picture>