{
  "id": "m0003",
  "title": "pipeline_conversations 补 session_id 列（会话隔离机制依赖）",
  "backup_tables": ["pipeline_conversations"],
  "up": [
    {"op": "sql", "sql": "ALTER TABLE pipeline_conversations ADD COLUMN session_id VARCHAR(32) NULL COMMENT '会话ID(多会话隔离)'"}
  ],
  "down": [
    {"op": "sql", "sql": "ALTER TABLE pipeline_conversations DROP COLUMN session_id"}
  ]
}