Describe the workflow you want to enable

In scikit-learn version 1.2, the set_output API was introduced. I would like to expose the API inside of the mlxtend.preprocessing.transactionencoder.TransactionEncoder class. This would allow the user to set the output of :method:TransactionEncoder.fit_transform and :method:TransactionEncoder.transform to a pandas.DataFrame by default, rather than having to manually create the object after transformation.

Describe your proposed solution

My proposed solution is to define the :method:get_feature_names_out in :class:TransactionEncoder as this is required to expose the :method:set_output. See :class:TransformerMixin and Developer API for set_output for more details.

Describe alternatives you've considered, if relevant

Continue using the method described in the User Guide—convert the output of the transformer to a pandas.DataFrame manually.

Additional context

• This would require the minimum version of scikit-learn to increase from 1.0.2 to 1.2.2.
• I'm willing to take on the PR for this work.