-- 通用资源退役，只关闭未来工作并释放活动订阅名额，不删除历史或审计；禁止外键。
ALTER TABLE pulse_queues
 ADD retired_at DATETIME(6) NULL COMMENT '永久退役时间，UTC；NULL表示未退役，退役后禁止新工作且不可恢复',
 ADD CONSTRAINT ck_queue_retired CHECK (retired_at IS NULL OR paused=TRUE);
ALTER TABLE orbit_subscriptions
 ADD retired_at DATETIME(6) NULL COMMENT '永久退役时间，UTC；NULL表示仍占用订阅名额，退役保留历史交付',
 ADD retired_sequence BIGINT UNSIGNED NULL COMMENT '退役事务锁定的结果流提交水位；NULL表示未退役，之后的事件不再订阅',
 ADD KEY ix_subscription_active(namespace_id,retired_at),
 ADD CONSTRAINT ck_subscription_retired CHECK ((retired_at IS NULL AND retired_sequence IS NULL) OR (retired_at IS NOT NULL AND retired_sequence IS NOT NULL AND enabled=FALSE AND pending_count=0));