- load Scala 3 compiler in sandboxed classloader.
  This change was added due to a conflict in
  reading the file compiler.properties.
- Add new erasure mode for Scala 3 intersection
  types
- Test erasure for constructors and SAM types
- Implement erasure for Arrays and test it

- enable scala 3 erasure for Type#erasure
- test intersection erasure with enums

- optimise dotty enum singleton erasure
- optimise dotty trait param checks

- It can be possible for a private local value
  to overload its field getter, so only select
  non-private local values
- also some refactorings

-also generate fresh wildcard name for wildcards

also document constructor
type params

it was a no-op in dotty