replace sed and awk with column options

[keturn]

column can handle manage setting the width of its columns, so we don't need to do that with awk and sed.

I think the specific -C option used here goes back to util-linux v2.39 around 2023, but we might be able to figure out other syntax that would work as far back as v2.30 if necessary.

Also switches the field delimiter so we don't have to worry about escaping /.