Module sync_tasks 

Durable sync tasks that Welcome processing and device sync enqueue inside their own storage transactions.

Functions

schedule_add_missing_installations

Durably enqueue one AddMissingInstallations task for group_id (deduped by payload hash against any pending row for the same group) and wake the TaskRunner. The task is due once delay, a rate-limit delay, has passed. A task until_done never expires, and a failing one backs off to at most one run an interval.

schedule_newcomer_adds

A new sync group from a Welcome means a new installation: schedule one durable task per eligible group, with bounded DM extras (deduped by payload hash), in the transaction that installs the Welcome, so a restart cannot lose them.