Diff information and Undo for Bao

I suggest looking at the model in harnesses, such as Visual Studio Code, which are used to manipulating content that is very important, and so have had to solve this issue over the recent past with strategies that wouldn't make people mad at losing their data.

For example, it exposes the concept of "Checkpoint" inline with the conversation, so that you can not only Undo items one at a time, but you can also rollback both the content and the conversation itself to a past point in the conversation, if you figure that things are going to a bad place.

Of course, Bao and Any have a few issues that Code does not have, because the checkpoint really rolls back in a lossy way, while the changes that Bao is working on are transactional and thus you are really applying additional reverts rather than simply going back. But perhaps it can be made to work well.

In either case, when we have agents that are capable of changing a lot at once in a not predictable way, being able to roll it all back easily is important indeed.

1. I asked bao to clean up an earlier failed attempt to set up a Collection. It then proceeded to delete everything except a new collection
2. I think after the fact would be fine, but it might also make sense to have different modes if people are more anxious. As long as I can undo, applying directly is fine.