Full multisig group state sync for new member of a SignifyGroupHab

[kentbull]

Feature request description/rationale

This is the KERIA issue for the similarly named issue in KERIpy: WebOfTrust/keripy#910

The rationale is the same. New participants in a multisig group need to have their local multisig group state synchronized to the latest state from the existing multisig group members. This includes:

All key event logs (similar to what kli local watch and kli multisig update currently do)
2. All credential registries.
3. All ACDC credentials
4. All signatures, attachments, indexes, or any other cryptographic material used for the multisig group that would be considered part of the multisig group identifier state.

All of this is mentioned in the referenced KERIpy ticket.