Support markdown for list item's title and description

[thomaslombart]

Describe the feature and the current behavior/state.

The original Linear extension had special formatting for issues that were done or canceled:

It seems the current version of the API doesn't allow any markdown in the List.Item component making it impossible to replicate this feature.

Will this change the current API? How?

Not sure if that would change the current API. Maybe there could be a prop to explicitly enable markdown in list items (like enableMarkdown for Textarea)

Who will benefit from this feature?

Any user who wants to benefit from more styling options in List.Item