verbresserung der verleih formulare und des RSS Feed

_includes/inventory-list.html

_includes/loaninfo.html

_includes/project-list.html

_layouts/device.html

_loan/20240509-schredder.md

_loancal/stickmaschine.md

_loancal/ultimaker.md

ausleihen.md

docs/content/inventory.md

inventory.xml