Include the tags in exported and imported opml

### Checklist

- [X] I have used the search function for [open](https://github.com/AntennaPod/AntennaPod/issues) **and** [closed](https://github.com/AntennaPod/AntennaPod/issues?q=is%3Aissue+is%3Aclosed) issues to see if someone else has already submitted the same bug report.
- [X] I will describe the problem with as much detail as possible.
- [X] If the bug only to occurs with a certain podcast, I will include the URL of that podcast.

### App version

2.6.2

### Where did you get the app from

F-Droid

### Android version

7.1.2 arm64

### Device model

Lenovo

### First occurred

_No response_

### Steps to reproduce

Exporting opml for use in desktop apps like newsboat which works with tags for cataloging the podcasts, doesn't include the specified tags in Antennapod , while exported opml in rssguard include all the tags which is recognizable by newsboat.

### Expected behaviour

The tags should be included in exported opml.

| ℹ️ | **Implementation instructions**|
|---|:---|
| | This request has been discussed further below. If you're interested in implementing this, please see the [conclusions relevant for implementation below](https://github.com/AntennaPod/AntennaPod/issues/6064#issuecomment-2526401366).
_{The original post has been edited by the project maintainers to add this link.} |

### Current behaviour

_No response_

### Logs

_No response_