Document how to deploy with scala-cli

[armanbilge]

scala-cli is extremely convenient for packaging a small Scala project into a deployable artifact (e.g. Jar or JS file). We should make some instructions how to do this and then how to actually deploy it.

[armanbilge]

Discord thread suggests that scala-cli --power package --assembly --preamble=false is the way to do it for a JVM Lambda.

https://discord.com/channels/632150470000902164/901153021638082660/1118988074383327284