Three-pass pull-sync (dm, friend, profile) from peer's /api/federation/sync endpoint, paginated. Seeds sinceTimestamp from peer.lastSyncedAt so a recovered peer pulls only the delta. Updates lastSyncedAt to Date.now() on full success; leaves it untouched on transient failure so the next activation retries the same window. Replaces the body of the soon-to-be-removed runInitialSyncForNewPeers.