Two listings folder by folder can't prove a backup holds every strategy
while another device moves them. The export now takes the user's own
library from strategies:listInventory, read in one server transaction:
it writes exactly the strategies the inventory lists, placed where it
says, with folder names and looks from the folder tree. A listed
strategy gone by the time it is fetched, or a folder the tree doesn't
hold where the inventory puts it, stops the export as a library that
changed mid-export. A folder shared with the user is not in their
inventory and is still listed folder by folder. The second-pass
comparison is gone.

Checking unsent work against the listed strategies missed work for a
strategy that had dropped out of the listing, such as an edit held for
review on a strategy deleted elsewhere. The export now waits until this
account has no cloud work left on this device, for any strategy, and
refuses if any remains.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>