feat(education): complete Flyway migration and atomic submit

sql/mysql/education/008-education-catalog-rollback.sql

@@ -0,0 +1,21 @@
+-- =============================================
+-- Education 模块 — 题库目录表回滚 DDL
+-- Ticket #20 rollback
+-- =============================================
+-- WARNING: This is an explicit data-destruction script.
+-- It is NOT part of application version rollback.
+-- Application version rollback preserves these tables and their data;
+-- this script is only used when permanently removing the catalog module.
+-- =============================================
+
+DROP TABLE IF EXISTS `education_question_collection_question`;
+DROP TABLE IF EXISTS `education_practice_blueprint`;
+DROP TABLE IF EXISTS `education_question`;
+DROP TABLE IF EXISTS `education_question_collection`;
+DROP TABLE IF EXISTS `education_content_node`;
+DROP TABLE IF EXISTS `education_content_entry`;
+DROP TABLE IF EXISTS `education_category`;
+DROP TABLE IF EXISTS `education_subject`;
+DROP TABLE IF EXISTS `education_major`;
+DROP TABLE IF EXISTS `education_school`;
+DROP TABLE IF EXISTS `education_region`;