We need to track when changes happen to notes in a more user-visible way, like how github does with ‘tag added, tag removed’ entries.

This should be attached to each note as a Log.

The structure of that log message is TBD.

I can see having entries like:

• reference added
• reference removed - but do we need these? github doesn’t show them?

the main things we want to do with this data is:

• show a ‘changelog’ of sorts (not the edits! just, meta changes)
• identify which things a thing references, so we can show that on those pages.
  • what links here / mentions this page
  • build a pretty network image.