- db: translate INSERT OR IGNORE ... SELECT to ON CONFLICT DO NOTHING;
register task_audit_loop_state (task_id) in _OR_REPLACE_PK (direct port).
- server: _backfill_default_quotas uses SAVEPOINT containment, no longer
commits the caller's transaction (direct port; callers are init_db only).
- worker: NOT ported — integration _coord_child_rows has no column-fallback
retry loop, so the InFailedSqlTransaction cascade site does not exist here.
- tests: rewritten for the integration base (no cloud.audit_loop /
_coord_audit_loop_merge here); real-PG cases skip without DSN/driver.
(cherry picked from commit 79e6843610fcd275af874e7b4afc57af7ffa579e)