chore(migration): 顺延分销迁移序号至 000066-000068，为 main 分支 000065 让路

backend/migrations/000068_file_upload_owners.sql

@@ -0,0 +1,17 @@
+-- +goose Up
+
+-- 私有文件上传归属：业务记录写入前，仅允许上传者预览自己的临时文件。
+CREATE TABLE file_upload_owners (
+  id BIGINT UNSIGNED NOT NULL AUTO_INCREMENT,
+  user_id BIGINT UNSIGNED NOT NULL,
+  object_key VARCHAR(512) NOT NULL,
+  created_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
+  PRIMARY KEY (id),
+  UNIQUE KEY uk_file_upload_owners_object_key (object_key),
+  KEY idx_file_upload_owners_user_id (user_id),
+  KEY idx_file_upload_owners_created_at (created_at)
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COMMENT='私有文件上传归属';
+
+-- +goose Down
+
+DROP TABLE IF EXISTS file_upload_owners;