Update non-ST FFI to use Fn

[JordanMartinez]

Description of the change

Updates non-ST FFI to use uncurried functions via Fn types

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Checklist:

• Added the change to the changelog's "Unreleased" section with a reference to this PR (e.g. "- Made a change (#0000)")
• Linked any existing issues or proposals that this pull request should close
• Updated or added relevant documentation
• Added a test for the contribution (if applicable)

[thomashoneyman]

What is the motivation for this? Just to write more idiomatic JS in the FFI? Is this a change we're going to apply across core?

[JordanMartinez]

Here's my rationale:

1. it produces stylistically cleaner JS output (no test needed)
2. Those doing dev work (i.e. just doing purs compile w/ no optimizations via purs-backend-es) should get code that runs faster (test needed to confirm)
3. once these functions use Fn* functions, purs-backend-es with no other changes should optimize more things (test needed to confirm)
4. once these functions use Fn* functions, purs-backend-es can be further updated to know how to evaluate some of these things during its optimization pass (pretty sure this is true).

[thomashoneyman]

Not considering this a relevant dependency change because this was already brought in transitively (but good we now have it listed)

[natefaubion]

once these functions use Fn* functions, purs-backend-es with no other changes should optimize more things (test needed to confirm)
once these functions use Fn* functions, purs-backend-es can be further updated to know how to evaluate some of these things during its optimization pass (pretty sure this is true).

Just as an FYI for changes like this, changing FFI calling conventions will potentially break optimizations. purs-backend-optimizer cases the calling convention against unsafeIndexImpl (curried vs uncurried matters), so currently the point release here very likely does not optimize at all with backend-es.

[natefaubion]

That is, if it's important for the core team (I'm not saying it is) to preserve optimizations in tools like backend-optimizer, it's important that we actually do follow up and verify the impact of these changes.