Whatever writes to a moving strategy, the original goes only if it is
still the object the move read: the check and the removal run with
nothing in between, and an original changed meanwhile stays next to its
cloud copy, with a message. A copy whose abandon failed stays locked
until cleanup removes it, and a local folder holding a moving strategy
can't be deleted until the move ends.

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