Task List with Batch Tasks triggers Exception

[thomaslow]

As part of the refactoring in #6906 I noticed that there is a dedicated page taskBatchEdit.xhtml for "batch" tasks. When opening the task list with a batch task, the following error message is shown:

jakarta.el.PropertyNotFoundException: Property [batchAvailable] not found on type [org.kitodo.data.database.beans.Task]
	at jakarta.el.BeanELResolver$BeanProperties.get(BeanELResolver.java:261)
	at jakarta.el.BeanELResolver.property(BeanELResolver.java:330)
	at jakarta.el.BeanELResolver.getValue(BeanELResolver.java:99)
	at jakarta.el.CompositeELResolver.getValue(CompositeELResolver.java:62)
...

Are batch tasks still a maintained feature of Kitodo.Production? The associated files (e.g. taskBatchEdit/taskEditDetails.xhtml seem to not have been updated for ~6 years.

The error above seems to be triggered because the property "batchAvailable" was formely stored inside the ElasticSearch index (see TaskDTO) and is now missing after the Hibernate-Search update. There seem to be no automated tests that check anything related to batch tasks.

To Reproduce
Steps to reproduce the behavior:

1. Create a workflow and mark the task as "batch task" (Stapelverarbeitung)
2. Create a process with this workflow
3. Navigate to the task list such that the batch task should be shown
4. See error

Expected behavior
There should be no error or the "batch task" feature should be removed completely.

Release
Tested with current main branch, but 3.9.X and above is probably affected