A signed-in session whose cloud setup fails because the server can't be
reached is now offline, not an incident. Setup tries again by itself when
the socket connects, and on a timer from 5 s to a minute. A session the
server rejects, or a build it refuses, behaves as before.

Every live answer of the folder tree and the strategy lists (My Library,
Shared, and the folders inside both) is written to cloud_library_copy_box,
keyed by deployment and account. While connecting or offline, the library
shows that copy, with a banner saying when it last matched the server.
Signing out deletes the account's copy.

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