Facet process to merge node types

Ran into this issue https://www.drupal.org/project/facets/issues/3368327 🐛 Facets Pretty Paths module and Merge node types processor error Active
Updated the patch slightly.

renamed the patch

Re-rolled the patch in #14 to improve the language used in comments and the UI. The functionality works great in the original patch.

For context we're using version 2.0.6 of facets, solr / solr cloud, and json:api search index.

Here's what we're seeing for the url of our merged node facet (in the metadata section of our json:api response):

https://base_url.com/jsonapi/index/solr_node_index?filter[facet_group]=facet_item&filter[0]=facet_group:facet_item&filter[1]=facet_group:facet_item

Which is not a clickable link.

Our patch corrects the generated url to the below:

https://base_url.com/jsonapi/index/solr_node_index?filter[facet_merged_name][condition][path]=facet_group&filter[facet_merged_name][condition][value][0]=facet_item_1&filter[facet_merged_name][condition][value][1]=facet_item_2&filter[facet_merged_name][condition][value][2]=facet_item_3

Which is a clickable link

Hopefully this patch helps resolve this issue for some others, if not

FYI the interdiff is in the previous comment and file 3133309-18.patch attached to this comment is the actual patch

Resolution to patch 19 which was attempting to pass the translate object as a query parameter

We already have a combine facets processor in 3.0.x. doesn't it solve the requirements here?

@mkalkbrenner the use case here is a common requirement by clients to group content types (and other fields) together in the same value for filtering, for example to produce a checkbox widget like so:

[ ] Latest
[ ] Articles
[ ] Documents

Where Latest are from content types blog and news, Articles are from content type article and page, and Documents are from document and file content type (just a quick example).

This can be done either at index time with a computed field or something, or at search time, with the work on this patch, I don't think it's the same as combining facets.