[Feature Request]: Live chat on the side in theatre mode

### Guidelines

- [X] I have searched the issue tracker for [open](https://github.com/FreeTubeApp/FreeTube/issues?q=is%3Aopen+is%3Aissue) and [closed](https://github.com/FreeTubeApp/FreeTube/issues?q=is%3Aissue+is%3Aclosed) issues that are similar to the feature request I want to file, without success.
- [X] I have searched the [documentation](https://docs.freetubeapp.io/) for information that matches the description of the feature request I want to file, without success.
- [X] This issue contains only one feature request.

### Problem Description

I use theatre mode by default and every time I view a livestream I have to toggle it off to see the live chat.

### Proposed Solution

Add the option to make live chat appear on the side while theatre mode is enabled, and also make the chat less wide in theatre mode so that the livestream does not get smaller.

### Alternatives Considered

n/a

### Issue Labels

new optional setting

### Additional Information

_No response_