Automatically switch to grid view for folders that contain only files of type media

### Actual behaviour
With Nextcloud I started to share quite a lot of my photos. Others upload photos as well. So I start having more and more folders filled with photos. As there are close to non open source webdav based gallery apps out there, the Nextcloud for android gets my primary photo gallery app. But it still has a drawback. I manually have to switch folders to grid view even there are no other files than photos. The grid view is by far the best view to watch photos. Other file functions are (luckily) also available in this view.

### Expected behaviour
The Nextcloud android app checks the type of all files that should be displayed in the current folder. If all files are from type "media", switch to the grid view automatically. Also nice: for someone who doesnt like this smart detection, an option in settings could prevent it.

### Steps to reproduce
1. Create a folder on the server
2. Upload only fotos
3. Navigate in the android app to this folder
4. Check if the folder is open in grid view

### Environment data
Android version: 7.1.2

Device model: BQ X5P

Stock or customized system: LineageOS

Nextcloud app version: 3.1.0

Nextcloud server version: 13.0.1

### Logs
#### Web server error log
```
-
```

#### Nextcloud log (data/nextcloud.log)
```
-
```