[Feature Request] Explore the use of hidden classes (JDK-15 and above) for Painless script classes generation.

[reta]

Is your feature request related to a problem? Please describe

Explore the use of hidden classes (JDK-15 and above) for Painless script classes generation.

Describe the solution you'd like

It provides a way to load a dynamically created classes at runtime without needing a new Classloader (that Painless compiler currently uses). Depends on #10745 since Apache Lucene 10 has JDK-17 baseline

Related component

Other

Describe alternatives you've considered

Keep the Painless class generation unchanged

Additional context

See please apache/lucene#1287