update Zeek to v8.1.0

[Zeek v8.1.0 is out](https://github.com/zeek/zeek/releases/tag/v8.1.0)

I've done most of the work on it already (see attached diff) but I'm going to save it for v26.02.0. Saving it here so I don't lose it.

There will probably be some of our parsers (or others) that will need to be fixed.

[zeek_810.diff](https://github.com/user-attachments/files/24624413/zeek_810.diff.txt)