Enrich Documentation with Screenshots and detail more some aspects

### Please check before submitting an issue

- [x] This issue is not related to the translated version of the documentation
- [x] I know technical terms used in the documentation

### Describe the problem area

Hi @MuntashirAkon

Thank you for your well crafted [documentation](https://muntashirakon.github.io/AppManager/en/) which is very helpful to get a grasp of your feature rich App.

Here are some proposals, as a non technical user, I am struggling a bit with those elements
**_1. Some items might need a screenshot for illustration_**
_**_2. Some special features might need to be documented_**_

### Current documentation if it present

[3.3 Backup/Restore](https://muntashirakon.github.io/AppManager/en/#toc:sec:backup-restore)
Especially the [Restore](https://muntashirakon.github.io/AppManager/en/#toc:subsec:backup-restore-restore) part, which is almost a one-liner.

And I couldn't find clear indications on how to batch install Apps either from .apk files or from a store (F-Droid, Obtainium, Aurora Store)

### Describe your suggestion

**_1. Some items might need a screenshot for illustration_**
- App's "landing screen" layout
- The bottom "action buttons" which are featured after long press on an App
- [3.3 Backup/Restore](https://muntashirakon.github.io/AppManager/en/#toc:sec:backup-restore)

Would you agree to provide some screenshots (I can help and share some in English and French language settings)

_**_2. Some special features might need to be documented_**_
- Special backups: SMS, Call Logs tracked in #973 : Might be helpfull to know the type of backup:
(full backup ?, full scheduled backup ?, incremental backup ?, incremental restore ?, full restore ?)

Again let me know if you might be interested in a "newbie's" perspective to help make your app accessible for that type of users

### Additional context

_No response_

Start with the English documentation at muntashirakon.github.io/AppManager/en/, especially the Backup/Restore and Restore sections, then review the batch-install flow and the SMS/Call Logs backup context in issue #973. Done means adding useful screenshots and expanding the restore, batch-install, and special-backup documentation with accurate coverage of full, scheduled, incremental, and restore behavior.

Written by the indexing model from the issue text.