Emit TypedBinders when inferring binders

[purefunctor]

Summary

When expressions are type checked, they usually yield TypedValue False e t. For the purposes of #4247, this makes it easy to figure out interval tree nodes as it's ultimately a matter of doing the following:

    onExpr :: Expr -> [InterfaceAST String]
    onExpr = \case
      TypedValue _ (PositionedValue s _ _) t ->
        [ makeNode (NodeInfo (debugType t) ExpressionNode) s ]
      _ ->
        []

Currently though, this doesn't seem to be the case with binders.