ENG-11250.
This adds basic support for displaying videos in DC threads.
Unfortunately, Farcaster uses HLS videos, which are a bit problematic. See test plan for how it works on different platforms.

Depends on D15342

• Mobile iOS and Android: Video is shown and is playable, the same as Comm native videos.
• Web Safari: Video works, HLS is natively supported by the browser
• Chromium-based web: Thumbnail is shown, but it's not playable.

General browser support: https://caniuse.com/http-live-streaming