Every ephemeral OfflineSyncDatabase shares one context but initializes a
recorder of its own, and each rebuilt the projections of every space
when the context's first initialize had changed the registry: on every
session and every merge, until the process stopped (upstream #150). A
new device, or one whose app changed its synced tables, spent about 3 s
of every inbound merge on it with a library of 8,000 cards, a server
after such a migration as much on every request.
The context now runs the rebuild once (Once): wrappers initializing
while it runs await the same run, later ones skip it, and a failed run
is tried again by the next.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
