Search not working properly with pre and post filters

Confirmed in a 5 mins with Zoran (modifying the data in the db) that the issue is with the field postNeuron that for the pre-synapses is empty. The query should look for the post in the field neuronsPost that contains the full list of neurons, this is required specifically for the pre-synapses.

Start by locating the search query handling pre-synapses and inspect how the post filter reads postNeuron versus neuronsPost. Reproduce the search with pre-synapse data, then verify that filtering uses the full neuronsPost list and returns the expected matches.

Written by the indexing model from the issue text.