uses: coordinates: be fully general over step inputs

[woodruffw]

#378 (comment) is an example of a false positive that we currently struggle to suppress, due to limitations to UsesCoordinate's expressiveness.

In particular, we can't currently express a condition like "this action is only relevant if foo: A and bar: B or baz: /regexp/."

To express those kinds of sentential logic chains we'll need to generalize UsesCoordinate::control to be something like controls instead, where controls will be a boolean expression of different propositions (basic matches, but also regular expressions).

I'm currently considering this low-ish priority, since doing it right is (1) tricky, and (2) only (so far) benefits a niche case that we can't yet analyze anyways (since cache-from: type=gha,ref=${{ github.run_id }} isn't something we can analyze yet).