Exact matches are not promoted in search results

Issue Summary

When performing a quick or advanced search, exact match results are not promoted in any way. Furthermore, other forms of the word will always be listed after any pages with "stemmed" version, no matter how recent or popular.

Steps to Reproduce

1. Create a page with word "Loader" in title (i.e. "Loader not working")
2. Create another with word "Load" in title (i.e. "Load a page")
3. Create a third page with word "load" in title (i.e can't load)
4. Search for "loader" (no quotes)

Expected Results

You get a page with word "Loader" in the title on top of your search results

Actual Results

You get search results for all pages containing the word "Load" because lucene stemmed the word when indexing, however, page with "Loader" in the title will not be in any way prioritised.

In fact, if you have more pages containing the word "load" in the title than can fit into quick search results, page title "Loader not working" will not appear in quick search at all
Furthermore, adding a new page called "Loading something" and searching for "loading" will not prioritise the new page either, despite it being more recent and closer matched keyword. It will also go to the bottom of the results after all the pages with "load" are listed

It appears that search algorithm prioritisation is ignoring exact matching as well as stemmed versions of the word

Notes

Exact match promotion was introduced in CONFSERVER-9261 request
Exact Search with double quotes is also not working as per CONFSERVER-68551 bug
Exact match promotion was still working in 6.13.23

Workaround

Currently there is no known workaround for this behavior. A workaround will be added here when available