Try to fix console and .repl

[lihaoyi]

Tries to fix #2704 by ensuring the system streams are properly inherited when running .console or .repl with -i.

Tested via

> ./mill show dev.launcher

> cd example/basic/1-simple-scala

> /Users/lihaoyi/Github/mill/out/dev/launcher.dest/run  -i console

Notably this cannot be tested via dev.run, because we would need to apply the same SystemStreams.withStreams(SystemStreams.original) wrapper to dev.run, which would first require re-bootstrapping Mill on top of this PR