`.environment(\.font, .custom(...))` type inference fails with a confusing error message

In SwiftUI, you can use the .environment() modifier to set a custom default font, like this:

.environment(\.font, .custom("Protest Guerrilla", size: 30.0))

But Skip has a type inference bug in this code: you have to call it with Font.custom() and not with simply .custom(), or it will fail to compile on Android.

I know that type-inference bugs are something I just have to deal with in Skip, but instead of saying, "Cannot infer type for this parameter", I get a really cryptic error message.

To reproduce this bug, I forked the Showcase app https://github.com/dfabulich/skipapp-showcase/tree/environment-font-bug-example and added a one-line commit: https://github.com/dfabulich/skipapp-showcase/commit/4d55295eeccc98e66e33a313b59d27ace864779c

Expected: Build fails with "Cannot infer type for this parameter" error

Actual:

Argument type mismatch: actual type is 'kotlin.Function1<ERROR CLASS: Unknown return lambda parameter type, ERROR CLASS: Unknown return lambda parameter type>', but 'kotlin.String' was expected.

Start with the linked Showcase app branch and its one-line commit reproducing the .environment(\.font, .custom(...)) call. Compare the expected type-inference diagnostic with the actual Kotlin error during the Android build; done means the failure reports "Cannot infer type for this parameter" instead of the cryptic type mismatch.