Allow forcing incompatible app versions

Sometimes apps lag behind in their support for newer Nextcloud versions. In case there are no real code incompatibilities, we'd like to be able to work around that by force-enabling an app, ignoring the formal incompatibility. For that we'll need to add an optional force attribute to the list items of the apps helm value.

To upload designs, you'll need to enable LFS and have an admin enable hashed storage. More information