Renaming of offline files treated as new files

### Actual behaviour
- When an "offline" file is renamed on the server, the app detects it as a completely new file. The "old" file is deleted from the cache, and a "new" file appears on the device (in the app) and must be downloaded again

### Expected behaviour
- The app should be able to detect that the file has just been renamed (or moved) and update its cache without re-downloading the file.
This probably requires some metadata-communication-channel between the server and the app, where the app can fetch a list of file-operations (moving, deleting etc) without basing sync solely on the file-list from the server.

### Steps to reproduce
1. Set a file as "Available offline" in the Android App
2. File is downloaded and cached locally on the device
3. Rename the file on the server (using the WEB UI or whatever other method - NOT the app)
4. Notice how the "new" file is not cached on the device

### Environment data
Android version: 7.1

Device model: Verified on Samsung, Sony and Lenovo

Stock or customized system: Stock

Nextcloud app version: 3.1.0

Nextcloud server version: 13.1

### Logs
#### Web server error log
```
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#### Nextcloud log (data/nextcloud.log)
```
Insert your Nextcloud log here
```
**NOTE:** Be super sure to remove sensitive data like passwords, note that everybody can look here! You can use the Issue Template application to prefill some of the required information: https://apps.nextcloud.com/apps/issuetemplate