Syntax highlighting for markdown fenced code blocks

[isidornygren]

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• Completed

Is your feature request related to a problem?

Fenced blocks in markdown does not seem to be highlighted, this might be due to them being part of the extended syntax and therefore not considered standard, or maybe it's just not implemented.
The extended syntax for markdown supports fenced code blocks which in my personal experience are widely used, and it would be great to have syntax highlighting for code blocks when working with things like readmes or data for static site builders.

Describe the solution you'd like

Render fenced code blocks with syntax highlighting based on the language defined after the first set of backticks (as defined in the markdown extended syntax), e.g:

```typescript
const some = "thing"; 
```

If applicable, add mockups / screenshots to help present your vision of the feature

How it currently looks in zed 0.60.3

How it looks like in vscode

[JosephTLyons]

Thank @isidornygren, this would be a fantastic addition.