Address last use of get_last_rowid

The `get_last_rowid` function is being called [here](https://github.com/AnswerDotAI/sqlite-minutils/blob/main/sqlite_minutils/db.py#L276-L279) in `insert_chunk`: https://github.com/AnswerDotAI/sqlite-minutils/blob/main/sqlite_minutils/db.py#L2992

That means that inserts are still vulnerable to corruption due to concurrency, transactions, and vacuums.

阅读 sqlite_minutils/db.py 第276-279行附近和第2992行，跟踪 get_last_rowid 和 insert_chunk。确定如何处理最后一次使用，同时避免插入操作在并发、事务或 vacuum 期间变得脆弱；完成标准是 insert_chunk 在这些情况下不再依赖 get_last_rowid。

由索引模型根据 Issue 内容生成。