Apply Scale sat there live and silent for the whole round trip, so on a large
slice the only sign anything was happening was the absence of a result -- and
a second click applied the change twice.
The button now spins, reads "Applying…", and refuses further clicks until the
write returns, with a line beside it saying the pivot updates when it
finishes. Cleared in a finally, so a failure releases it too.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>