Issues with "Citybikes" and "Scooters" Selection in German and English Versions

[stadtnavimanager]

### Webversion: @hbruch

Description:
There are two main issues with the "Citybikes" and "Scooters" selection in the settings of the stadtnavi web version.

1. Selection Issue: It is not possible to deselect both options simultaneously. Users are forced to select at least one of the options ("RegioRad" or "TIER Ludwigsburg").

2. Translation Issue: The translation from German to English is incorrect and incomplete. Specifically:
   The German term "Leihräder und Scooter" translates to "Rental bikes and scooters" rather than "Citybikes". If this translation is too long, consider using "Sharing" as an alternative.

Steps to Reproduce:
Go to the stadtnavi web version.
Open the settings.
Try to deselect both "RegioRad" and "TIER Ludwigsburg".

Expected Behavior:
Users should be able to deselect both options if they choose to do so.
The English translation should accurately reflect the German terms. ("Rental bikes and scooters" or "Sharing" if this is too long)

### stadtnavi-App @Denis306
Since it is displayed differently in the app, only the translation of "Citybikes" to "Rental bikes and scooters" should be changed here (if possible regarding the length).

Thank you for addressing these issues!