55814ee introduced calls to sliceUnits() in the recode and clone routes
without ever defining it, so both have thrown "sliceUnits is not defined"
since that commit. Scale worked only because it inlined the same three lines
rather than calling the helper.
Defined from scale's copy, and scale now calls it too. Recode and clone
passed req.body.apply_mode straight through, where scale normalised it
first, so an absent or unrecognised value would have fallen to the 'each'
branch by accident; they normalise the same way now.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>