[Feature Request]: Make certain settings persistent

### Guidelines

- [x] I have [searched the issue tracker for open and closed issues](https://github.com/FreeTubeApp/FreeTube/issues?q=is%3Aissue+sort%3Arelevance-desc) 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.
- [x] I have read and agree to follow the [rules](https://docs.freetubeapp.io/community/rules/).

### Problem Description

There are many options available to users on the Settings page. Some settings feel unnecessary to list and can be handled better imo.

### Proposed Solution

If last state of a setting can be easily remembered then make the setting persistent. This also means that the option will be removed in the settings page with the added bonus of making the settings page less bloated.

Settings that come to mind are:
- Theme -> Expand Side Bar by Default
- Player -> Enable Subtitles by Default
- Player -> Autoplay Recommended Videos
- Player -> Autoplay Playlist Videos
- Player -> Default viewing mode (most of them)
- Player -> Default video format
- Player -> Default quality
- Player -> Default volume
- Player -> Default playback rate

### Alternatives Considered

None.

### Issue Labels

ease of use improvement

### FreeTube Version

https://github.com/FreeTubeApp/FreeTube/commit/e856e36c11700dea38a855ccd1f4deb9346484b5

### Operating System Version

Windows 11 IoT Enterprise LTSC 24H2

### Installation Method

.exe

### Upload screenshots or videos

_No response_

### Additional Information

_No response_

Start at the Settings page and trace the listed Theme and Player options into the corresponding playback behavior. Determine how each current setting is stored and used, then verify that the listed preferences persist across sessions and that only the intended redundant options are removed from Settings.

Written by the indexing model from the issue text.