Wire up `--debug-adapter` for JVM languages

[thejcannon]

Both run and test goals now have a --debug-adapter which should launch the relevant DAP server when used. We should add support for JVM (feel free to split into multiple tickets for Java+Scala+Friends, idk how the DAP in JVM-world works)

See the Python support for examples, or ping @thejcannon

[thejcannon]

FYI @tdyas

[tdyas]

DAP bridge for JVM debugging is https://github.com/Microsoft/java-debug.

[stuhood]

And this would be a significant part of #15965, because Metals requires DAP for test running.

[pshemass]

for scala we could use - https://github.com/scalacenter/scala-debug-adapter. I could try to add this for scala if someone will help me.