Local file selector's slowly load didn't cancel after switched to another folder and showed after loaded

### ⚠️ 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 big folder that include lots of files (my is DCIM\Camera which contains 9707 pictures)
2. Create a small folder that include just some files (my is DCIM\ImageApp contains 32 pictures)
3. Click Add Button, Select Upload files from App and select big folder
4. During loading, navigate to small folder

### Expected behaviour

File selector show files in small folder.

### Actual behaviour

File selector show files in small folder for a while.

After big folder loaded it show files in big folder and top of the app still show small folder's name

### Android version

15

### Device brand and model

SAMSUNG Galaxy S22

### Stock or custom OS?

Stock

### Nextcloud android app version

3.31.3

### Nextcloud server version

Nextcloud Hub 10 (31.0.5)

### Using a reverse proxy?

No

### Android logs

[logcatOutput.txt](https://github.com/user-attachments/files/20562582/logcatOutput.txt)

### Server error logs

```bash

```

### Additional information

Reproduce Video Record

https://www.youtube.com/watch?v=DM-CgOd2lGs

Beginne damit, den Race mit den bereitgestellten großen und kleinen Ordnern unter Android 15 zu reproduzieren, und verwende dabei die verknüpfte logcat-Ausgabe und das Video für Details zum Timing. Verfolge die Einstiegspunkte für die Ordnernavigation und das Laden des lokalen Dateiauswählers und überprüfe anschließend, dass ein früherer Ladevorgang nach der Navigation nicht die Dateien des aktuell ausgewählten Ordners ersetzen kann.

Vom Indexierungsmodell aus dem Issue-Text verfasst.