feat: add video player using react-player to support YouTube, Vimeo and other sources

[qtangs]

Building on the idea suggested by @postonsundays at https://github.com/Chainlit/chainlit/pull/686.

What can be done now:

• [x] Display videos from various sources provided by ReactPlayer (YouTube, Facebook, Twitch, Vimeo, DailyMotion, ...)
• [x] Custom config for each type of player as supported by ReactPlayer for further enhancements, for example, auto play and custom start time for YouTube videos.

[qtangs]

This is how it looks with 3 videos from the test: https://github.com/Chainlit/chainlit/blob/51be1a324fac1f82d1376fa95461589624daaf14/cypress/e2e/video_element/main.py#L6-L41

[willydouhard]

Do we have to specify the player config? Can't react-player auto detect the kind of video it is?

[qtangs]

Yes, that's already the case, react-player can auto detect based on url. The player config is optional, it's added to show how to customize settings like autoplay and start time.

[qtangs]

Ah, there's a branch conflict now. I'll fix it but can @willydouhard or someone from the team review this soon so we avoid new conflicts?

[tpatel]

Waiting on the automated tests to merge your PR.