Scala codegen enhancements

• Merge pull request #408 from AttilaMihaly/issue-407 45b7448
• Make sure locally defined variables are also taken into account to avoid name clashes. #407 b643013
• Fix issues with curried case class constructors. Replace structural type with constructor when the specific type is known. #407 108b729

v2.25.1...v2.26.0