File uploaded as attachment to text file is not readily accessible

### ⚠️ Before posting ⚠️

- [x] This is a **bug**, not a question or an enhancement.
- [x] I've [searched for similar issues](https://github.com/nextcloud/android/issues) and didn't find a duplicate.
- [x] I've written a clear and descriptive title for this issue, not just "Bug" or "Crash".
- [x] I agree to follow Nextcloud's [Code of Conduct](https://nextcloud.com/contribute/code-of-conduct/).

### Steps to reproduce

Make a folder with a ``.md`` file in it.
Share the folder with a link with write access.
Have somebody upload a file as an attachment to the ``.md`` file.
In the Android client, open the folder (not through the link).

### Expected behaviour

I do not know really. This cements my idea that [attachments to ``.md`` files are bad](https://github.com/nextcloud/text/issues/8479).

Maybe show that an attachment was added to the file in the home screen, where recent activity is displayed.

### Actual behaviour

The file appears on the client welcome screen as a recently edited file, and can be opened from there. But it does not show up in the folder itself, unless one has checked the option to show hidden files, because it resides in a ``.attachment-xxx`` subfolder.

### Android version

16

### Device brand and model

pixel 7a

### Stock or custom OS?

Stock

### Nextcloud android app version

33.0.1

### Nextcloud server version

33

### Additional information

It is not sure whether the method for sharing the folder has an influence.