v1.37.3
Fix: eliminate cross-platform sync state race. Concurrent syncs (cron firing all platforms at once) were racing on the shared .one/sync/sync_state.json — failed renames wedged models in status=syncing, and the read-modify-write could silently lose an update. State is now stored per-platform/per-model at .one/sync/state/<platform>/<model>.json so each writer owns its own file. Legacy file is migrated on first read.