v1.1.0

• Support Psalm 7: TKeyedArray's constructor is private there, so shapes are
  built through TKeyedArray::make() (which Psalm 6 has from 6.19). The
  vimeo/psalm constraint widens to ^6.19 || ^7.0. The Returns integration
  fixture now accepts InvalidScalarArgument, which is what Psalm 7 calls the
  wrong-callback-return case Psalm 6 filed as InvalidArgument.