Support function defs as function values (for factory dependencies)

It would be nice if function defs were automatically converted to function values.

So that with the following class:

class PlatformsPage(store:PlatformStore,platformBackend:(BackendScope[Props,State] => Backend))

You could wire its dependencies with a module like:

trait PlatformsModule {
  lazy val platformsPage = wire[PlatformsPage]
  lazy val platformsStore = wire[PlatformStore]
  def platformsBackend(scope:BackendScope[Props,State]):Backend = new Backend(scope)
}

There are easy alternatives:

lazy val platformsBackend:BackendScope[Props,State] => Backend = new Backend(_)

type BackendFactory = BackendScope[Props,State] => Backend
lazy val platformsBackend:BackendFactory = new Backend(_)

But given that defs are used with MacWire, it seems like it would be nice to support function defs as function value dependencies.

The issue names no source files or tests. Start by locating MacWire's handling of function definitions and function-valued dependencies; done means a def like platformsBackend can satisfy the function-valued constructor dependency, with coverage for the shown wiring.