use rtx-nodejs fork with proper aliases for lts-hydrogen

[jdx]

we should adopt the nodejs rtx fork so that we have the aliases which will work better than the symlinks that currently are used in nodejs.

This helps with updates since right now if you want to use the latest version of "lts-hydrogen" you would have to run rtx i nodejs@lts-hydrogen -f I think. Aliases would avoid this and rtx would map "lts-hydrogen" to the latest version of 18.x, not just whatever version it installed.

I think we should also add an alias for "lts" which can be helpful with #286, that way we can do the following:

rtx i nodejs@lts nodejs@lts~2

to get the 2 most recent lts releases. It would be nice to also be able to express "all non-eol releases", but at least right now I'm unsure how to do that.