Time spent in the 'find module with suffix' portion of our `customResolve` function were adding up to around 100ms-150ms when booting the app. This time is spread over 150+ calls, so it's not immediately obvious in flamegraphs.
This commit implements a (reversed) [Trie](https://en.wikipedia.org/wiki/Trie) which enables fast suffix-based lookups on a list of strings.
In my tests, this requires < 5ms to initialize, and brings the cumulative 'find module with suffix' time down to `< 5ms`. This corresponds to a ~100ms improvement in LCP metrics in my browser.
The only behavior change is to remove support for module filenames which are **not** dasherized. I haven't found any core/theme/plugin modules which are not dasherized in their filenames.
This is to help with the migration to Ember CLI. In the current running
version of Discourse everything should be the same as before, just with
a few extra files that are not used. However, using Ember CLI this can
be installed as an Ember addon.
Co-Authored-By: Jarek Radosz <jradosz@gmail.com>
