water/server/scripts/migrate_water_routing.php

<?php
/** 仅增加路线优化元数据及短期预览表，保留全部原业务数据。 */
require dirname(__DIR__).'/vendor/autoload.php';
\Dotenv\Dotenv::createUnsafeMutable(dirname(__DIR__))->load();
\support\App::loadAllConfig(['route']);
use support\Db;
if (!in_array('--apply',$argv,true)) { echo "Plan: add nullable route optimization JSON text and route preview table. No data deletion.\n"; exit; }
if (!Db::select("SHOW COLUMNS FROM sa_water_route LIKE 'optimization'")) Db::statement('ALTER TABLE sa_water_route ADD COLUMN optimization LONGTEXT NULL');
Db::statement("CREATE TABLE IF NOT EXISTS sa_water_route_preview (
 id BIGINT UNSIGNED AUTO_INCREMENT PRIMARY KEY, token CHAR(64) NOT NULL, actor_id BIGINT UNSIGNED NOT NULL,
 tasks_hash CHAR(64) NOT NULL, payload LONGTEXT NOT NULL, expires_at DATETIME NOT NULL,
 UNIQUE KEY preview_token(token), KEY preview_expiry(expires_at)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4");
echo "Applied additive route optimization migration.\n";