Remember search string after selecting and opening a file from search results

### ⚠️ 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 and checked most recent issues)_.
- [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

The sequence I often have is:

1. search for "foo", find it in several places
2. click the line I'm interested in
3. file opens, but at the top; the string appears much later, so I have to type it in again to get there.

Would be nice if it just went to the line I clicked on the in the search results dialog, or at least pre-populated the search box with the same string I used to get here.

### Information

Android version:
Device (phone model):
App Version:

### Source

F-Droid

### Format / File type

Not specific

### Additional info / Log

```shell
-
```

Start at the search-results dialog and follow the flow used when a result line is selected and its file opens. Reproduce the "foo" sequence, then verify that opening a result preserves the selected line or pre-populates the search box with the original query.

Written by the indexing model from the issue text.