Sync silently fails when special characters are used in a filename

### ⚠️ 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

1. Put files with special characters '?', '<', or '>' in a cloud folder
1. Sync that folder on android
2. Get one "Error occurred while downloading files" notification for every file with such a name, every time sync occurs
3. Observe that everything is synced except the files with the special characters are NOT downloaded
4. Rename the files by removing the characters. Observe that they're now synced.

The issue has been around for many months now.

### Expected behaviour

The files should be synced, or if not, a descriptive notification saying which file is affected and what is the issue

### Actual behaviour

Files are not downloaded

### Android version

15

### Device brand and model

Pixel 7

### Stock or custom OS?

Stock

### Nextcloud android app version

3.31.1

### Nextcloud server version

30.0.6

### Using a reverse proxy?

I don't know

### Android logs

_No response_

### Server error logs

```bash

```

### Additional information

_No response_