hacked it around for redmine 5.0.14, ruby 3.1

[mcr]

I had to do a bunch of munging of params, had to init @query in the controller, and a context-menu call changed. I have patches that I'll turn into a PR as soon as we've run it for a few days. We had been running redmine 4.2.9, with original ecdavis plugin. This plugin seems equivalent, but the appearance is different, but maybe our ecdavis plugin was even older.