same scroll position between edit and view mode

### ⚠️ This issue respects the following points: ⚠️

- [x] This is a **enhancement/feature request**. Not a [bug or question](https://github.com/gsantner/markor/issues/new/choose).
- [x] The topic is **not** already reported at [Issues](https://github.com/gsantner/markor/issues?q=#js-issues-search). _(I've searched it)_.
- [x] Markor **is** up to date. See [Releases](https://github.com/gsantner/markor/tags) for the latest version. Updates are available from [F-Droid](https://f-droid.org/en/packages/net.gsantner.markor/) and GitHub.
- [x] The wanted feature/enhancement is not present in the latest development version (git master). (Please [download](https://nightly.link/gsantner/markor/workflows/build-android-project/master) and try the test version of Markor, named **Marder**. Don't worry; Markor and Marder appear as completely separate applications. You can install both side-by-side, and Markor's settings are not touched. If your desired feature is present, you don't need to open this issue. The change will be part of the next Markor update.)

### Description

It would be great to be able to switchback back and switch back and forth between view and edit mode and have the scroll position at the same line. As it is now when I'm in view mode and switch to edit mode, I have to scroll to get to the same position.

### Information

Android version:
Device:
App Version:

### Source

F-Droid

### Format / File type

Not specific

### Additional info / Log

```shell
-
```

No file or test is identified in the issue. Start by locating the entry points for switching between view and edit mode and trace how each mode handles scrolling. Done means switching in either direction preserves the same document line or scroll position.

Written by the indexing model from the issue text.