update：修改ai_agent_chat_history表content字段类型为TEXT

main/manager-api/src/main/resources/db/changelog/202603311200.sql

@@ -0,0 +1,2 @@
+-- 修改聊天内容字段类型
+ALTER TABLE ai_agent_chat_history MODIFY COLUMN content TEXT COMMENT '聊天内容';

main/manager-api/src/main/resources/db/changelog/db.changelog-master.yaml

@@ -571,3 +571,10 @@ databaseChangeLog:
         - sqlFile:
             encoding: utf8
             path: classpath:db/changelog/202603111131.sql
+  - changeSet:
+      id: 202603311200
+      author: cgd
+      changes:
+        - sqlFile:
+            encoding: utf8
+            path: classpath:db/changelog/202603311200.sql