events: index actor events by actor ID rather than f4 addr

[rvagg]

Ref: #11594

WIP, notes:

• This doesn't have a migration, it just starts from a new schema, I started looking at what that would do and there's a little bit of work on a test framework for index migrations. That looked like a fun problem to try and solve and have tests for it.
• There's an unresolved question in this: what kind of address do we provide back to the user on their events? This PR has a two-way translation, such that your inputs can be non-ID addresses and they'll get translated, but your events will be translated to addresses if they can be, or ID addresses if not. I'm unsure of what the appropriate UX is here.
• Revisiting this after a month I'm not so confident in the timing of the look-ups - are they being done at the correct tipset wherever we do a translation (see Index Actor Events by ID #11594 for notes about this).

[rvagg]

better version @ #11723