[SPIKE] Investigate supporting Java 8

[skeet70]

Java 8 seems to be the common target for libraries. We're currently using Java 20+ features in our generated code. Investigate and report here on what features we'd need to lose, what can be polyfilled, and what functionality we would lose.

Discuss the tradeoffs, create tickets if we decide to support it.

[BobWall23]

Could figure out the effort to support back to Java 17 - that is likely to be a problem because we are using Records, and they are new after 17. If we can get to 17, getting back to 11 or 8 is probably not too difficult.