fix(firstleg): retain declaration event idempotency history

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

@@ -839,6 +839,17 @@ CREATE TABLE IF NOT EXISTS fl_order_declaration_snapshot (
   KEY idx_order_declaration_version (tenant_id, order_id, order_version)
 ) ENGINE=InnoDB COMMENT='Order客户申报版本快照；与箱码、实测、托盘、PDA和计费事实隔离';
 
+CREATE TABLE IF NOT EXISTS fl_order_declaration_event (
+  tenant_id BIGINT UNSIGNED NOT NULL COMMENT '客户ID和隔离键',
+  event_id VARCHAR(128) NOT NULL COMMENT '永久保留的Order Outbox事件ID',
+  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),
+  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';
+
 CREATE TABLE IF NOT EXISTS fl_customer_dimension_config (
   id BIGINT UNSIGNED NOT NULL COMMENT '配置ID',
   tenant_id BIGINT UNSIGNED NOT NULL COMMENT '客户ID和数据隔离键',