补齐统一数据库中文注释

firstleg/src/main/resources/db/phase2-inbound-schema.sql

@@ -832,8 +832,8 @@ CREATE TABLE IF NOT EXISTS fl_order_declaration_snapshot (
   cargoes_json JSON NOT NULL COMMENT '客户申报货物行完整快照，不覆盖实测事实',
   changes_json JSON NULL COMMENT '本版本申报字段变化摘要',
   occurred_at DATETIME(3) NOT NULL COMMENT 'Order事件发生时间',
-  created_at DATETIME(3) NOT NULL DEFAULT CURRENT_TIMESTAMP(3),
-  updated_at DATETIME(3) NOT NULL DEFAULT CURRENT_TIMESTAMP(3) ON UPDATE CURRENT_TIMESTAMP(3),
+  created_at DATETIME(3) NOT NULL DEFAULT CURRENT_TIMESTAMP(3) COMMENT '快照创建时间',
+  updated_at DATETIME(3) NOT NULL DEFAULT CURRENT_TIMESTAMP(3) ON UPDATE CURRENT_TIMESTAMP(3) COMMENT '快照更新时间',
   PRIMARY KEY (tenant_id, order_id),
   UNIQUE KEY uk_order_declaration_event (tenant_id, event_id),
   KEY idx_order_declaration_version (tenant_id, order_id, order_version)
@@ -845,7 +845,7 @@ CREATE TABLE IF NOT EXISTS fl_order_declaration_event (
   order_id BIGINT UNSIGNED NOT NULL COMMENT 'Order订单ID',
   order_version INT NOT NULL COMMENT '事件携带的Order聚合版本',
   request_hash CHAR(64) NOT NULL COMMENT '完整事件SHA-256，用于异参重放拒绝',
-  consumed_at DATETIME(3) NOT NULL DEFAULT CURRENT_TIMESTAMP(3),
+  consumed_at DATETIME(3) NOT NULL DEFAULT CURRENT_TIMESTAMP(3) COMMENT '事件消费完成时间',
   PRIMARY KEY (tenant_id, event_id),
   KEY idx_order_declaration_event_order (tenant_id, order_id, order_version)
 ) ENGINE=InnoDB COMMENT='Order客户申报事件永久幂等账本';