fix(storage): make queue and object ownership durable

migrations/026_idempotency_operation_leases.sql

@@ -0,0 +1,11 @@
+ALTER TABLE idempotency_keys
+  ADD COLUMN lease_owner UUID,
+  ADD COLUMN lease_until TIMESTAMPTZ;
+
+ALTER TABLE idempotency_keys
+  ADD CONSTRAINT idempotency_keys_lease_pair_check
+  CHECK ((lease_owner IS NULL) = (lease_until IS NULL));
+
+CREATE INDEX idempotency_keys_stale_operations
+  ON idempotency_keys(lease_until)
+  WHERE response_status = 0;