feat(governance): distribute committee invitations based on address (WIP)

[dckc]

This DRAFT PR is mostly to let @Chris-Hibbert see what this looks like; he has some reasonable hesitation about whether this is in scope for the committee contract.

In #4348 (RUN protocol governance demo), we have:

3. choose a few addresses for economic committee members and a chair/secretary
4. make a governance proposal to start the RUN protocol and seat the committee

This adds support in the committee contract to send voter invitations to deposit facets based on address.

In combination with a few changes in other packages, it lets us do:

$ agoric start local-solo
# copy address from log output

Then in another terminal, the chain operator designates the committee members:

$ addrs=agoric1lf7u6rm0ssvt6rqm3mas5n3syj4mefek7py4dy # space separated list
$  ECON_GOV_ADDRS=$addrs agoric start local-chain --reset -v

Then (after a few minutes) in the wallet corresponding to the local-solo, in our Zoe invitation purse, we get a voter invitation.

[Chris-Hibbert]

That looks quite plausible. I can imagine an ElectionManager having code to distribute the invitations after the election concludes.