Crash when uploading a file into an e2e encrypted folder

### ⚠️ 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. create a folder from the android app and set it to encrypted (already here I need to close and reopen the app to see that the folder is encrypted)
2. open the folder
3. try to upload a file
4. app crashes

### Expected behaviour

file should be uploaded correctly

### Actual behaviour

app crashes when trying to upload and displays the logs (attached in this post under "Android Logs")

### Android version

16

### Device brand and model

Samsung S25

### Stock or custom OS?

Stock

### Nextcloud android app version

33.0.1

### Nextcloud server version

33.0.1

### Using a reverse proxy?

Yes

### Android logs

### Cause of error
```java
Exception in thread "Thread-44" java.lang.IllegalStateException: metadata is null!
at com.owncloud.android.operations.RefreshFolderOperation.synchronizeData(RefreshFolderOperation.java:546)
at com.owncloud.android.operations.RefreshFolderOperation.fetchAndSyncRemoteFolder(RefreshFolderOperation.java:464)
at com.owncloud.android.operations.RefreshFolderOperation.run(RefreshFolderOperation.java:275)
at com.owncloud.android.lib.common.operations.RemoteOperation.run(RemoteOperation.java:387)
at java.lang.Thread.run(Thread.java:1564)

```

### App information
* ID: `com.nextcloud.client`
* Version: `330000190`
* Build flavor: `gplay`

### Device information
* Brand: `samsung`
* Device: `pa1q`
* Model: `SM-S931B`
* Id: `BP2A.250605.031.A3`
* Product: `pa1qxeea`

### Firmware
* SDK: `36`
* Release: `16`
* Incremental: `S931BXXS8BZB5`

### Server error logs

```bash

```

### Additional information

_No response_