LSO kiosk player: finish on last step, show sequence title and item description

[kevenClausenKPG]

Summary

 - Shows the learning sequence title in the kiosk player context/curriculum instead of the generic curriculum label.                     
 - Displays the current item's description on the kiosk page when available.                                                             
 - Changes the final navigation step so the player offers `Finish` on the last item instead of continuing with `Next`.                   

Related Issues

 - https://mantis.ilias.de/view.php?id=46242                                                                                             
 - https://mantis.ilias.de/view.php?id=34620