PDF Files öffnen sich nicht im PDF viewer

### ⚠️ 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

.

### Expected behaviour

Hi,

Bei mir lassen sich über die nextcloud Android Client v.34.0.1 App PDF Files nicht öffnen bzw werden im PDF viewer nicht angezeigt.

Nextcloud Server 34.0.1

### Actual behaviour

.

### Android version

Android 17

### Device brand and model

Google Pixel 7a

### Stock or custom OS?

Stock

### Nextcloud android app version

34.0.1

### Nextcloud server version

34.0.1

### Using a reverse proxy?

I don't know

### Android logs

_No response_

### Server error logs

```bash

```

### Additional information

_No response_

Start by reproducing PDF opening in the Nextcloud Android app using app and server version 34.0.1 on the listed Pixel 7a and Android 17, then collect the missing Android and server logs. Trace the PDF viewer entry point and compare the failing behavior with another supported file type; done means PDFs open and render in the viewer.

Written by the indexing model from the issue text.