include deliverynum/syscallnum in anachrophobia errors

[warner]

What is the Problem Being Solved?

Investigating #6588 would be easier if the error we displayed included both the deliveryNum and the syscallNum of the mismatch. Even better would be more context: include the previous few syscalls actually made, and the previous/next few syscalls expected. Like a diff --unified instead of just the first line of a regular diff.

Description of the Design

Change vat-loader/transcript.js to show more information.

Security Considerations

none, the transcript is common knowledge, and the messages are only displayed on stderr (and the kernel panics immediately afterwards)

Test Plan

A unit test would be nice, but I don't think we currently exercise this error pathway very much.