Variation alternates not processed for statics

I'm not sure whether this is intentional, but it feels a lot like an oversight:
`ufo2ft` (both stable release as well as repo version) isn’t processing the alternates for static fonts, see below (static vs. variable).


The master UFO do contain the relevant substitutions (and they work in variable):
```xml






















```

Always happy to help with further debugging. It's a commercial font so I can't post a source but can invite you to my repo.

No project file or test is named. Start by tracing ufo2ft's static-font handling of conditional substitutions and compare it with the variable-font path; use the supplied substitutions as the expected behavior and add a regression test once a reproducible fixture is available.

Written by the indexing model from the issue text.