新增 family_invite 家庭邀请码表(schema+0009迁移)

Co-Authored-By: Claude Haiku 4.5 <noreply@anthropic.com>

drizzle/0009_family-invite.sql

@@ -0,0 +1,11 @@
+-- xuchao: 家庭邀请码——家长生成一次性邀请码,其他家长凭码注册加入家庭。幂等。
+CREATE TABLE IF NOT EXISTS `family_invite` (
+	`id` bigint AUTO_INCREMENT NOT NULL,
+	`family_id` bigint NOT NULL,
+	`code_hash` varchar(64) NOT NULL,
+	`created_by` bigint NOT NULL,
+	`created_at` datetime NOT NULL DEFAULT CURRENT_TIMESTAMP,
+	`expires_at` datetime NOT NULL,
+	`used_at` datetime,
+	CONSTRAINT `family_invite_id` PRIMARY KEY(`id`)
+);